A 100-MIPS GaAs asynchronous microprocessor

The authors describe how they ported an asynchronous microprocessor previously implemented in CMOS to gallium arsenide, using a technology-independent asynchronous design technique. They introduce new circuits including a sense-amplifier, a completion detection circuit, and a general circuit structure for operators specified by production rules. The authors used and tested these circuits in a variety of designs

A General Approach to Performance Analysis and Optimization of Asynchronous Circuits

A systematic approach for evaluating and optimizing the performance of asynchronous VLSI circuits is presented. Index-priority simulation is introduced to efficiently find minimal cycles in the state graph of a given circuit. These minimal cycles are used to determine the causality relationships between all signal transitions in the circuit. Once these relationships are known, the circuit is then modeled as an extended event-rule system, which can be used to describe many circuits, including ones that are inherently disjunctive. An accurate indication of the performance of the circuit is obtained by analytically computing the period of the corresponding extended event-rule system

An Asynchronous Microprocessor in Gallium Arsenide

In this paper, several techniques for designing asynchronous circuits in Gallium Arsenide are presented. Several new circuits were designed, to implement specific functions necessary to the design of a full microprocessor. A sense-amplifier, a completion tree, and a general circuit structure for operators specified by production rules are introduced. These circuit were used and tested in a variety of designs, including two asynchronous microprocessors and two asynchronous static RAM's. One of the microprocessor runs at over 100 MIPS with a power consumption of 2 Watts

Observation of First-Order Metal-Insulator Transition without Structural Phase Transition in VO_2

An abrupt first-order metal-insulator transition (MIT) without structural phase transition is first observed by current-voltage measurements and micro-Raman scattering experiments, when a DC electric field is applied to a Mott insulator VO_2 based two-terminal device. An abrupt current jump is measured at a critical electric field. The Raman-shift frequency and the bandwidth of the most predominant Raman-active A_g mode, excited by the electric field, do not change through the abrupt MIT, while, they, excited by temperature, pronouncedly soften and damp (structural MIT), respectively. This structural MIT is found to occur secondarily.Comment: 4 pages, 4 figure

Burden of Human papillomavirus (HPV)-related disease and potential impact of HPV vaccines in the Republic of Korea

Background: We aimed to review the burden and the potential impact of human papillomavirus (HPV) vaccines on HPV-related diseases in the Republic of Korea and to discuss cervical cancer prevention practices in this country. Methods: Cancer burden statistics were retrieved from GLOBOCAN-2018 and Statistics Korea. HPV disease burden was assessed via systematic review. Vaccine types relative contribution (RC) was estimated using data from an international project using formalin-fixed paraffin-embedded specimens. Results: Despite a downtrend in cervical cancer in recent years, Korean rates remain high. In contrast, oropharyngeal cancer incidence has gradually increased and other anogenital cancers remain rare. In Korea, HPV prevalence in general population is around 20%. In cervical cancer, RC of HPVs 16/18 (74.0%) increased to 92.0% when including HPVs 31/33/45/52/58. Limited information was available for other HPV-related cancer sites. Regarding prevention, since the inclusion of the HPV vaccine into the National Immunization Program, almost half (49%) of the target cohort in 2016 had received the first dose of vaccine. Further, percentage of women screened with pap has increased from 41.1%-2009 to 53.0%-2016. Conclusions: HPV-related disease burden in Korea is significant. Results suggest that the combination of effective and high coverage HPV vaccination and screening programmes could substantially impact on HPV-related disease in Korea

The Spill-Over Impact of the Novel Coronavirus-19 Pandemic on Medical Care and Disease Outcomes in Non-communicable Diseases: A Narrative Review

OBJECTIVES: The coronavirus-19 (COVID-19) pandemic has claimed more than 5 million lives worldwide by November 2021. Implementation of lockdown measures, reallocation of medical resources, compounded by the reluctance to seek help, makes it exceptionally challenging for people with non-communicable diseases (NCD) to manage their diseases. This review evaluates the spill-over impact of the COVID-19 pandemic on people with NCDs including cardiovascular diseases, cancer, diabetes mellitus, chronic respiratory disease, chronic kidney disease, dementia, mental health disorders, and musculoskeletal disorders. METHODS: Literature published in English was identified from PubMed and medRxiv from January 1, 2019 to November 30, 2020. A total of 119 articles were selected from 6,546 publications found. RESULTS: The reduction of in-person care, screening procedures, delays in diagnosis, treatment, and social distancing policies have unanimously led to undesirable impacts on both physical and psychological health of NCD patients. This is projected to contribute to more excess deaths in the future. CONCLUSION: The spill-over impact of COVID-19 on patients with NCD is just beginning to unravel, extra efforts must be taken for planning the resumption of NCD healthcare services post-pandemic

Clinical Effectiveness of Urinary Human Chorionic Gonadotropin Related Protein (hCGRP) Quantification for Diagnosis of Ectopic Pregnancy

We detected pregnancy related new molecule, human chorionic gonadotropin related protein (hCGRP) in the urine of a pregnant women by using a monoclonal antibody against the human chorionic gonadotropin (hCG). This study examined the effectiveness of urinary hCGRP quantification in diagnosing ectopic pregnancy. This study included 40 normal pregnant women and 25 patients with ectopic pregnancy. Patients' serum and urinary intact whole hCG (i-hCG) and hCGRP concentrations were measured using sandwich ELISA and the ratio of hCGRP to i-hCG was calculated. Statistical analysis was performed using statistical package for social sciences (SPSS) 10.0. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the cut-off value to discriminate ectopic pregnancies from normal intrauterine pregnancies. Urinary hCGRP and hCGRP/i-hCG ratio in ectopic pregnancy group (14±6.6 ng/mL, 4.6±1.9%, respectively) were significantly lower than those of normal pregnancy group (149±10.2 ng/mL, 29.7±1.9%, respectively; p<0.001). Based on ROC curve analysis, a cut-off point of urinary hCGRP/i-hCG ratio <16.2% discriminated between ectopic pregnancy and normal pregnancy with a sensitivity, specificity, positive predictive value and negative predictive value of 92.0%, 90.0%, 32.6%, and 99.5%, respectively. Urinary hCGRP/i-hCG ratio measurement may be effective in diagnosing ectopic pregnancy

Macrolide resistance and genotypic characterization of Streptococcus pneumoniae in Asian countries: a study of the Asian Network for Surveillance of Resistant Pathogens (ANSORP)

Objectives: To characterize mechanisms of macrolide resistance among Streptococcus pneumoniae from 10 Asian countries during 1998-2001. Methods: Phenotypic and genotypic characterization of the isolates and their resistance mechanisms. Results: Of 555 isolates studied, 216 (38.9%) were susceptible, 10 (1.8%) were intermediate and 329 (59.3%) were resistant to erythromycin. Vietnam had the highest prevalence of erythromycin resistance (88.3%), followed by Taiwan (87.2%), Korea (85.1%), Hong Kong (76.5%) and China (75.6%). Ribosomal methylation encoded by erm(B) was the most common mechanism of erythromycin resistance in China, Taiwan, Sri Lanka and Korea. In Hong Kong, Singapore, Thailand and Malaysia, efflux encoded by mef(A) was the more common in erythromycin-resistant isolates. In most Asian countries except Hong Kong, Malaysia and Singapore, erm(B) was found in >50% of pneumococcal isolates either alone or in combination with mef(A). The level of erythromycin resistance among pneumococcal isolates in most Asian countries except Thailand and India was very high with MIC90s of >128 mg/L. Molecular epidemiological studies suggest the horizontal transfer of the erm(B) gene and clonal dissemination of resistant strains in the Asian region. Conclusion: Data confirm that macrolide resistance in pneumococci is a serious problem in many Asian countries