Background: On 31 December 2019 an outbreak of COVID-19 in Wuhan, China, was reported. The outbreak spread rapidly to other Chinese cities and multiple countries. This study described the spatio-temporal pattern and measured the spatial association of the early stages of the COVID-19 epidemic in mainland China from 16 January-06 February 2020. Methods: This study explored the spatial epidemic dynamics of COVID-19 in mainland China. Moran's I spatial statistic with various definitions of neighbours was used to conduct a test to determine whether a spatial association of the COVID-19 infections existed. Results: The spatial spread of the COVID-19 pandemic in China was observed. The results showed that most of the models, except medical-care-based connection models, indicated a significant spatial association of COVID-19 infections from around 22 January 2020. Conclusions: Spatial analysis is of great help in understanding the spread of infectious diseases, and spatial association was the key to the spatial spread during the early stages of the COVID-19 pandemic in mainland China.

No abstract

A silk nanofiber‐networked bio‐triboelectric generator (Silk Bio‐TEG) is developed using an eco‐friendly and sustainable silk biomaterial with strong hydrogen bonding between peptide blocks. The electrospun Silk Bio‐TEG shows highly durable and reliable energy harvesting performances due to its notably high surface‐to‐volume ratio, mechanically super‐strong silk fibers, and fracture tolerant behavior of nanofiber‐networks.

Background-The vasoconstrictor peptide endothelin-1 (ET-1) is important for increased vascular tone in patients with chronic heart failure, but the effects of endothelin-receptor blockade in addition to conventional triple therapy are unknown. Methods and Results-Thirty-six men (mean ageϮSD, 55Ϯ8 years) with symptomatic heart failure (NYHA class III; left ventricular ejection fraction, 22.4Ϯ4.5%) despite treatment with diuretics, digoxin, and ACE inhibitors received, in a double-blind and randomized fashion, either additional oral bosentan (1.0 g BID; nϭ24) or placebo (nϭ12) over 2 weeks. Hemodynamic and hormonal (plasma ET-1, norepinephrine, renin activity, and angiotensin II) measurements were obtained before and repeatedly for 24 hours after administration of bosentan on days 1 and 14. Bosentan was discontinued in 1 patient with symptomatic hypotension, and 2 patients (bosentan group) declined hemodynamic investigations on day 14. Heart rate remained unchanged. Plasma ET-1 levels increased after bosentan, but baseline levels of the other hormones were unchanged. Conclusions-Additional short-term oral endothelin-receptor antagonist therapy improved systemic and pulmonary hemodynamics in heart failure patients who were symptomatic with standard triple-drug therapy. Further investigations are warranted to characterize the effects of long-term endothelin-receptor antagonist therapy on symptoms, morbidity, and mortality in such patients. (Circulation. 1998;98:2262-2268.)

AbstractÐEfficient and effective buffering of disk blocks in main memory is critical for better file system performance due to a wide speed gap between main memory and hard disks. In such a buffering system, one of the most important design decisions is the block replacement policy that determines which disk block to replace when the buffer is full. In this paper, we show that there exists a spectrum of block replacement policies that subsumes the two seemingly unrelated and independent Least Recently Used (LRU) and Least Frequently Used (LFU) policies. The spectrum is called the LRFU (Least Recently/Frequently Used) policy and is formed by how much more weight we give to the recent history than to the older history. We also show that there is a spectrum of implementations of the LRFU that again subsumes the LRU and LFU implementations. This spectrum is again dictated by how much weight is given to recent and older histories and the time complexity of the implementations lies between O(1) (the time complexity of LRU) and ylog P n (the time complexity of LFU), where n is the number of blocks in the buffer. Experimental results from trace-driven simulations show that the performance of the LRFU is at least competitive with that of previously known policies for the workloads we considered.

Background Many countries have implemented non-pharmaceutical interventions (NPIs) to slow the spread of coronavirus disease 2019 (COVID-19). We aimed to determine whether NPIs led to the decline in the incidences of respiratory infections. Methods We conducted a retrospective, ecological study using a nationwide notifiable diseases database and a respiratory virus sample surveillance collected from January 2016 through July 2020 in the Republic of Korea. Intervention period was defined as February–July 2020, when the government implemented NPIs nationwide. Observed incidences in the intervention period were compared to the predicted incidences by autoregressive integrated moving average model and the 4-year mean cumulative incidences (CuIs) in the same months of the pre-intervention period. Results Five infectious diseases met the inclusion criteria: chickenpox, mumps, invasive pneumococcal disease, scarlet fever, and pertussis. The incidences of chickenpox and mumps during the intervention period were significantly lower than the prediction model. The CuIs of chickenpox and mumps were 36.4% (95% CI, 23.9–76.3) and 63.4% (95% CI, 48.0–93.3) of the predicted values. Subgroup analysis showed that the decrease in the incidence was universal for chickenpox, while mumps showed a marginal reduction among those aged <18 years, but not in adults. The incidence of respiratory viruses was significantly lower than both the predicted incidence (19.5%; 95% CI, 11.8–55.4%) and the 4-year mean CuIs in the pre-intervention period (24.5%; P<0.001). Conclusions The implementation of NPIs was associated with a significant reduction in the incidences of several respiratory infections in Korea.

Numerous studies indicate that regular intake of polyphenol-rich beverages (red wine and tea) and foods (chocolate, fruit, and vegetables) is associated with a protective effect on the cardiovascular system in humans and animals. Beyond the well-known antioxidant properties of polyphenols, several other mechanisms have been shown to contribute to their beneficial cardiovascular effects. Indeed, both experimental and clinical studies indicate that polyphenols improve the ability of endothelial cells to control vascular tone. Experiments with isolated arteries have shown that polyphenols cause nitric oxide (NO)-mediated endothelium-dependent relaxations and increase the endothelial formation of NO. The polyphenol-induced NO formation is due to the redox-sensitive activation of the phosphatidylinositol3-kinase/Akt pathway leading to endothelial NO synthase (eNOS) activation subsequent to its phosphorylation on Ser 1177. Besides the phosphatidylinositol3-kinase/Akt pathway, polyphenols have also been shown to activate eNOS by increasing the intracellular free calcium concentration and by activating estrogen receptors in endothelial cells. In addition to causing a rapid and sustained activation of eNOS by phosphorylation, polyphenols can increase the expression level of eNOS in endothelial cells leading to an increased formation of NO. Moreover, the polyphenol-induced endothelium-dependent relaxation also involves endothelium-derived hyperpolarizing factor, besides NO, in several types of arteries. Altogether, polyphenols have the capacity to improve the endothelial control of vascular tone not only in several experimental models of cardiovascular diseases such as hypertension but also in healthy and diseased humans. Thus, these experimental and clinical studies highlight the potential of polyphenol-rich sources to provide vascular protection in health and disease.

Regional heating of the pelvic area with mEHT significantly increased the peri-tumour temperature and improved the blood flow in cervical cancer. This is the first demonstration that the blood flow in cervical cancer is increased by regional hyperthermia. Such increases in temperature and blood flow may account for the clinical observations that hyperthermia improves the response of cervical cancer to radiotherapy or chemotherapy.