China empowers mobile health technologies to fight against COVID-19 pandemic. The success of mobile health here may be a useful reference for other parts of the world. We explore China's application of mobile health technologies to replenishing traditional public-health and social approaches for mitigating and suppressing COVID-19, and found that Internet hospitals alleviate the unavailability, inaccessibility, and inequity of health services during the outbreak; the fact-check and information-release platforms reduce the spread of misinformation; and the infection risk scoring systems facilitate restoring the order of production and life.

Background Internet hospitals in China are being rapidly developed as an innovative approach to providing health services. The ongoing COVID-19 pandemic has triggered the development of internet hospitals that promote outpatient service delivery to the public via internet technologies. To date, no studies have assessed China's internet hospitals during the COVID-19 pandemic. Objective This study aimed to elucidate the characteristics of China's internet hospitals and assess the health service capacity of these hospitals. Methods Data on 711 internet hospitals were collected from official websites, the WeChat (Tencent Inc) platform, smartphone apps, and the Baidu search engine until July 16, 2020. Results As of July 16, 2020, 711 internet hospitals were developed in mainland China. More than half of these internet hospitals (421/711, 59.2%) were established during 2019 (206/711, 29%) and 2020 (215/711, 30.2%). Furthermore, about one-third (215/711, 30.2%) of internet hospitals were established at the beginning of 2020 as an emergency response to the COVID-19 epidemic. The 711 internet hospitals consisted of the following 3 types of hospitals: government-oriented (42/711, 5.91%), hospital-oriented (143/711, 20.11%), and enterprise-oriented internet hospitals (526/711, 73.98%). The vast majority of internet hospitals were traditional hospitals (526/711, 74%). Nearly 46.1% (221/711) of internet hospitals requested doctors to provide health services at a specific web clinic. Most patients (224/639, 35.1%) accessed outpatient services via WeChat. Internet hospitals’ consulting methods included SMS text messaging consultations involving the use of graphics (552/570, 96.8%), video consultations (248/570, 43.5%), and telephone consultations (238/570, 41.8%). The median number of available web-based doctors was 43, and the median consultation fees of fever clinics and other outpatient clinics were ¥0 (US $0) per consultation and ¥6 (US $0.93) per consultation, respectively. Internet hospitals have provided various services during the COVID-19 pandemic, including medical prescription, drug delivery, and medical insurance services. Conclusions The dramatic increase of internet hospitals in China has played an important role in the prevention and control of COVID-19. Internet hospitals provide different and convenient medical services for people in need.

The worldwide severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak has led to the rapid spread of coronavirus disease (COVID-19). The quantitative real time PCR (qPCR) is widely used as the gold standard for clinical detection of SARS-CoV-2. However, more and more infected patients are relapsing after discharge, which suggests qPCR may fail to detect the virus in some cases. In this study, we selected 74 clinical samples from 43 recovering inpatients for qPCR and Droplet Digital PCR (ddPCR) synchronous blind detection, and established a cutoff value for ddPCR diagnosis of COVID-19. The results showed that at a cutoff value of 0.04 copies/μL, the ddPCR sensitivity and specificity are 97.6% and 100%, respectively. In addition, we also analyzed 18 retained samples from 9 discharged patients who relapsed. Although qPCR showed all 18 samples to be negative, ddPCR showed 12 to be positive, and there was only one patient with two negative samples; the other eight patients had at least one positive sample. These results indicate that ddPCR could significantly improve the accuracy of COVID-19 diagnosis, especially for discharged patients with a low viral load, and help to reduce misdiagnosis during recovery.

The aeolian landforms in the Qaidam Basin have drawn increasing attention from geomorphologists for their morphological and formation mechanisms' similarities with their counterparts on Mars and Titan. Using grain-size and mineral composition data, this study investigated the source of aeolian dune sands found on the northern margin of Qarhan Salt Lake in the south central part of the Qaidam Basin. Results indicate that linear dune sands and gobi surface sediments are mainly composed of fine and very fine sands, while the yardang corridor sands are much coarser, with medium and fine sands in predominance. The curves of the linear dune sands show a standard normal distribution pattern. This is also the case for the gobi surface sediments and yardang corridor sands located away from linear dunes. However, the curves for these two sediment types show much wider kurtoses. The distribution curves for the yardang corridor sands located near the linear dunes are different from the above-mentioned sediments, which explicitly display bimodal distributions. More mineral types were detected in the yardang corridor sands and gobi surface sediments than in dune sands.But the major mineral compositions of the three kinds of sediments are similar. Contents of typical very stable and stable heavy minerals differ little among the three sediments, while the contents of some heavy minerals with poor stability differ greatly.The relative proportions of quartz, plagioclase, and orthoclase in all three kinds of sediments demonstrate that they all likely originated from the granite and granodiorite rocks of the Qilian Mountain ranges. Therefore, gobi surface sediments and yardang corridor sands near the study linear dune field could be the source of dune sands. Further investigations are needed to determine whether the yardang corridor sands far away from the study linear dune field feed dunes in the Sebei area.

Underlying terrain strongly influences dune formation. However, the impacts of underlying terrain on the dune formation are poorly studied. In the present research, we focused on dunes that formed in the alluvial fans and dry salt flats in the Qaidam Basin, Northwest China. We quantified the dunes' sediment characteristics on different types of underlying terrain and the terrain's effects on the surface quartz grains by analyzing grain-size distribution, soluble salt contents and grain surface micro-textures. Results showed that barchan dunes were dominated by medium sands with a unimodal frequency distribution, whose peak corresponded to the saltation load. Linear dunes were mainly composed of fine sands with a bimodal frequency distribution, whose main peak represented the saltation load, and whose secondary peak represented the modified saltation or suspension load. Sand was transported from source area by running water (inland rivers) over short distances and by wind over relatively longer distances. Thus, quartz grains had poor roundness and were dominated by sub-angular and angular shapes. Surface micro-textures indicated that dune sands were successively transported by exogenic agents (glaciation, fluviation and wind). Soluble salt contents were low in dunes that developed in the alluvial fans, which represented a low-energy chemical environment, so the grain surface micro-textures mainly resulted from mechanical erosion, with weak micro-textures formed by SiO 2 solution and precipitation. However, soluble salt contents were much higher in dunes that developed in the dry salt flats, which indicated a high-energy chemical environment. Therefore, in addition to micro-structures caused by mechanical erosion, micro-textures formed by SiO 2 solution and precipitation also well developed. Our results improve understanding of the sediment characteristics of dune sands and the effects of underlying terrain on dune development in the Qaidam Basin, China.

Mobile health applications are emerging as a novel platform to obtain data pertinent to wellness and disease diagnosis, prevention, and management. As the future general trend of medical informatization, mobile health is an indispensable way to promote universal medical care to reduce disease burden. The features of these mHealth apps in China is unclear, so we collected a wide range of application information to evaluate these apps effectively.

BACKGROUND The Internet hospital is rapidly developing in China as an innovative approach to providing health services. The corona virus disease 2019 (COVID-19) outbreak has boost the process because Internet hospital has the ability to provide widespread accessible outpatient service delivery via Internet technologies for the public during the epidemic. To date, China's Internet hospitals during the COVID-19 pandemic have not been systematically investigated. OBJECTIVE The aim of this study is to understand the characteristics of China's Internet hospitals, and to assess their health service capacity. METHODS Using “Internet hospitals”, “Internet health”, “Internet medicine”, “mobile medicine”, “mobile health”, “Telehealth”, “digital medicine”, “digital health”, “Web hospitals”, and “Cloud hospitals” in Chinese as the search terms, the data of Internet hospitals were collected via official website, the WeChat platform, smartphone app and the Baidu search engine until July, 2020. RESULTS By July 2020, the number of Internet hospitals had expanded to 714 in 31 provinces. Of the 714 Internet hospitals, the half of Internet hospitals were established in 2019 (206, 28.85%) and 2020 (215, 30.11%). Especially, Internet hospitals set up in the beginning of 2020, as an emergency response to the COVID-19 epidemic, has a one-third weight in the final total. There are three different dominators—government-oriented, hospital-oriented, and enterprise-oriented internet hospitals—for which sponsors have different characters of supporting content and responsibilities. In the vast majority of Internet hospitals, traditional hospitals have dominant position (73.67%, 526/714). In addition, patients accessed outpatient service delivery via WeChat (224, 35.05%) most widely. 221 (46.14%) of Internet hospitals asked doctors to give health services at a specific Web clinic, while 258(53.86%) by smartphone app. The consulting methods included graphic message (96.84%), video (43.51%) and telephone (41.75%). Besides, 106(18.60%) Internet hospitals offered 3 ways to consult for patients at the same time. The median number of doctors available online was 43. The median consultation fee of fever clinic and other outpatient clinics except fever clinic per time were separately ¥0 and ¥6. Four-fifths(80.94%) of doctors were from local hospitals and medical union. Internet hospitals played various roles during COVID-19, such as medical prescription, drug delivery service, medical insurance, epidemic prevention and control information, fever clinic consultation, psychological counseling, myth busters of COVID-19, epidemic situation dynamic and donation. CONCLUSIONS Internet hospitals are booming in China. Internet hospital play an important role on preventing and controlling COVID-19, providing different and convenient types of medical services for people seeking medical needs.