326 research outputs found
Supporting Learning and Working in Disastrous Pandemics by Smart Technologies: A Qualitative Analysis
During the breakout of coronavirus disease (COVID-19), smart technologies were perceived to provide convenience and assistance for people, enterprises, and government units. Although there is literature maintaining that smart technology can facilitate pandemic strategy and response in ways that are difficult to achieve manually, some other literature indicated that smart technologies were not desirable alternatives to people during this pandemic. MIS education is a career preparation for IT professionals who use smart technology in organizations. IT professionals with MIS education backgrounds may have important roles when facing COVID-19. Moreover, many MIS students will become IT professionals and join the workforce for combatting the pandemic using smart technologies with their background of MIS education. This study intends to analyze smart technology utilization in the confrontation of the COVID-19 pandemic with a qualitative approach. The results could provide reflective insights for MIS education providers, human resource units, IT firms, and organizations confronting COVID-19 outbreaks
A COMPARISON OF BALANCE CONTROL BETWEEN JAVELIN THROWERS AND BASEBALL PITCHERS
This study evaluated the balance control in javelin throwers and baseball pitchers. Twenty-four athletes took part in the study and for each we measured their static and dynamic balance by Biodex Balance System, AMTl AccuSway force plate and Y balance test. The paired t-test was conducted to compare all the variables within subjects. The independent t-test was used to compare trail leg (TL) of baseball pitchers with propulsive leg (PL) of javelin throwers and stride leg (SL) of baseball pitchers with braking leg (BL) of javelin throwers. The results showed that there was no difference between the PL and BL in dynamic and static balance in javelin throwers. However, the dynamic balance in the TL was significantly better than the SL in baseball pitchers. The static balance in the PL in javelin throwers was also better than the TL in baseball pitchers. The research improves the understanding of balance control in elite athletes
Src-homology 2 domain-containing tyrosine phosphatase 2 promotes oral cancer invasion and metastasis
BACKGROUND: Tumor invasion and metastasis represent a major unsolved problem in cancer pathogenesis. Recent studies have indicated the involvement of Src-homology 2 domain-containing tyrosine phosphatase 2 (SHP2) in multiple malignancies; however, the role of SHP2 in oral cancer progression has yet to be elucidated. We propose that SHP2 is involved in the progression of oral cancer toward metastasis. METHODS: SHP2 expression was evaluated in paired oral cancer tissues by using immunohistochemical staining and real-time reverse transcription polymerase chain reaction. Isogenic highly invasive oral cancer cell lines from their respective low invasive parental lines were established using a Boyden chamber assay, and changes in the hallmarks of the epithelial-mesenchymal transition (EMT) were assessed to evaluate SHP2 function. SHP2 activity in oral cancer cells was reduced using si-RNA knockdown or enforced expression of a catalytically deficient mutant to analyze migratory and invasive ability in vitro and metastasis toward the lung in mice in vivo. RESULTS: We observed the significant upregulation of SHP2 in oral cancer tissues and cell lines. Following SHP2 knockdown, the oral cancer cells markedly attenuated migratory and invasion ability. We observed similar results in phosphatase-dead SHP2 C459S mutant expressing cells. Enhanced invasiveness was associated with significant upregulation of E-cadherin, vimentin, Snail/Twist1, and matrix metalloproteinase-2 in the highly invasive clones. In addition, we determined that SHP2 activity is required for the downregulation of phosphorylated ERK1/2, which modulates the downstream effectors, Snail and Twist1 at a transcript level. In lung tissue sections of mice, we observed that HSC3 tumors with SHP2 deletion exhibited significantly reduced metastatic capacity, compared with tumors administered control si-RNA. CONCLUSIONS: Our data suggest that SHP2 promotes the invasion and metastasis of oral cancer cells. These results provide a rationale for further investigating the effects of small-molecule SHP2 inhibitors on the progression of oral cancer, and indicate a previously unrecognized SHP2-ERK1/2-Snail/Twist1 pathway that is likely to play a crucial role in oral cancer invasion and metastasis
Cytomegalovirus enteritis in immunocompetent patients: Report of two cases diagnosed using single-balloon enteroscopy
SummaryCytomegalovirus (CMV) infection of the gastrointestinal tract involves mostly the colon and rectum and mainly develops in immunocompromised patients. CMV infection in the small intestines has rarely been reported in immunocompetent patients. We report two cases of CMV enteritis that developed in immunocompetent patients and involved the ileum and jejunum, respectively. Both of them were diagnosed with single-balloon enteroscopy (SBE) and further confirmed with histopathology. The first case is a 71-year-old woman with a presentation of obscure gastrointestinal bleeding and severe anemia. Neither esophagogastroduodenoscopy nor colonoscopy identified any active bleeding. SBE and biopsy disclosed multiple scattered ulcers in the distal ileum and histopathology confirmed CMV ileitis. The hemorrhage subsided after conservative medical treatment. The second case is a 59-year-old woman with a presentation of progressive abdominal pain. SBE showed diffuse irregularly-shaped ulcers located from the upper to middle jejunum, and CMV jejunitis was confirmed with endoscopic biopsy and histopathological examination. Antiviral therapy was prescribed and her abdominal pain improved gradually. We discuss the clinical manifestations and management strategies of CMV infection that develops in the small intestines of immunocompetent patients. In addition, we highlight the endoscopic characteristics of CMV enteritis and the clinical utilities of SBE in the evaluation of patients with suspected CMV infection of the small intestines
The Uses of a Dual-Band Corrugated Circularly Polarized Horn Antenna for 5G Systems
This paper presents the development of a wide-beam width, dual-band, omnidirectional antenna for the mm-wave band used in 5G communication systems for indoor coverage. The 5G indoor environment includes features of wide space and short range. Additionally, it needs to function well under a variety of circumstances in order to carry out its diverse set of network applications. The waveguide antenna has been designed to be small enough to meet the requirements of mm-wave band and utilizes a corrugated horn to produce a wide beam width. Additionally, it is small enough to integrate with 5G communication products and is easy to manufacture. This design is simple enough to have multi-feature antenna performance and is more useful for the femtocell repeater. The corrugated circularly polarized horn antenna has been designed for two frequency bands; namely, 26.5–30 GHz for the low band and 36–40 GHz for high band. The results of this study show that return-loss is better than 18 dB for both low and high band. The peak gain is 6.1 dBi for the low band and 8.7 dBi for the high band. The beam width is 105 degrees and 77 degrees for the low band and the high band, respectively. The axial ratio is less than 5.2 dB for both low and high band. Generally, traditional circularly polarized antennas cannot meet the requirements for broadband. The designs for the antennas proposed here can meet the requirements of FR2 bandwidths. This feature limits axial ratio performance. The measurement error in the current experiment comes from the high precision control on the size of the ridge
Adsorption and thermal decomposition of H 2 S on Si(1 0 0)
Abstract Adsorption and thermal decomposition of H 2 S on Si(1 0 0)-2 Â 1 are studied by means of temperature-programmed desorption (TPD) and X-ray photoemission spectroscopy (XPS) with synchrotron radiation. The H 2 S molecule dissociates to form H and HS on the Si surface at adsorption temperature of 115 K. The Si(1 0 0)-2 Â 1 surface structure is conserved upon the adsorption of H 2 S due to bonding of dissociative H and HS on two Si atoms in a dimer without breaking the Si-Si dimer bond. H 2 and SiS are the only desorption products of thermal decomposition of H 2 S with peaks at 780 and 820 K, respectively. On the basis of TPD and XPS results, intermediates involved in decomposition of H 2 S and their adsorption configurations are proposed and discussed
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