The Spatio-Temporal Evolution of Food Production and Self-Sufficiency in China from 1978 to 2020: From the Perspective of Calories.

Ensuring national food security is an eternal topic. We unified six categories of food with calorie content including grain, oil, sugar, fruits and vegetables, animal husbandry, and aquatic products on the basis of provincial-level data, and we dynamically evaluated caloric production capacity and the supply-demand equilibrium under the increase in feed-grain consumption as well as the food losses and waste in China from 1978 to 2020 at four different levels. The results show that: (1) From the perspective of food production, the total national calorie production showed a linear growth trend, with a growth rate of 31.7 × 1012 kcal/year, of which the proportion of grain crops has always exceeded 60%. Most provinces showed significant increasing trends in food calorific production, except for Beijing, Shanghai, and Zhejiang, which showed slightly decreasing trends. The distribution pattern of food calories and their growth rate were high in the east and low in the west. (2) From the perspective of the food supply-demand equilibrium, the national food calorie supply has been in surplus since 1992, but significant spatial heterogeneity is detected, with the Main Marketing Region changing from a tight balance to a short surplus, North China always remaining in calorie shortage, and 15 provinces still presenting supply and demand gaps up to 2020, necessitating the establishment of a more efficient and faster flow and trade system. (3) The national food caloric center has shifted 204.67 km to the northeast, and the population center has shifted to the southwest. The reverse migration of the centers of food supply and demand will further aggravate the pressure on water and soil resources and cause higher requirements for ensuring the circulation and trade system of food supply. The results are of great significance for the timely adjustment of agricultural development policies, making rational use of natural advantages and ensuring China's food security and sustainable agricultural development.

Reinforcement learning assisted oxygen therapy for COVID-19 patients under intensive care.

BACKGROUND: Patients with severe Coronavirus disease 19 (COVID-19) typically require supplemental oxygen as an essential treatment. We developed a machine learning algorithm, based on deep Reinforcement Learning (RL), for continuous management of oxygen flow rate for critically ill patients under intensive care, which can identify the optimal personalized oxygen flow rate with strong potentials to reduce mortality rate relative to the current clinical practice. METHODS: We modeled the oxygen flow trajectory of COVID-19 patients and their health outcomes as a Markov decision process. Based on individual patient characteristics and health status, an optimal oxygen control policy is learned by using deep deterministic policy gradient (DDPG) and real-time recommends the oxygen flow rate to reduce the mortality rate. We assessed the performance of proposed methods through cross validation by using a retrospective cohort of 1372 critically ill patients with COVID-19 from New York University Langone Health ambulatory care with electronic health records from April 2020 to January 2021. RESULTS: The mean mortality rate under the RL algorithm is lower than the standard of care by 2.57% (95% CI: 2.08-3.06) reduction (P < 0.001) from 7.94% under the standard of care to 5.37% under our proposed algorithm. The averaged recommended oxygen flow rate is 1.28 L/min (95% CI: 1.14-1.42) lower than the rate delivered to patients. Thus, the RL algorithm could potentially lead to better intensive care treatment that can reduce the mortality rate, while saving the oxygen scarce resources. It can reduce the oxygen shortage issue and improve public health during the COVID-19 pandemic. CONCLUSIONS: A personalized reinforcement learning oxygen flow control algorithm for COVID-19 patients under intensive care showed a substantial reduction in 7-day mortality rate as compared to the standard of care. In the overall cross validation cohort independent of the training data, mortality was lowest in patients for whom intensivists' actual flow rate matched the RL decisions.

Infection fatality ratio and case fatality ratio of COVID-19.

The infection fatality ratio (IFR) is the risk of death per infection and is one of the most important epidemiological parameters. Enormous efforts have been undertaken to estimate the IFR for COVID-19. This study examined the pros and cons of several approaches. It is found that the frequently used approaches using serological survey results as the denominator and the number of confirmed deaths as the numerator underestimated the true IFR. The most typical examples are South Africa and Peru (before official correction), where the confirmed deaths are one-third of the excess deaths. We argue that the RT-PCR-based case fatality ratio (CFR) is a reliable indicator of the lethality of COVID-19 in locations where testing is extensive. An accurate IFR is crucial for policymaking and public-risk perception.

Changes in RT-PCR test results and symptoms during the menstrual cycle of female individuals infected with SARS-CoV-2: Report of two cases.

The implications of the menstrual cycle for disease susceptibility, development, and severity of acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are largely unknown. Here, we describe two women infected with SARS-CoV-2 whose real-time reverse transcriptase-polymerase chain reaction (RT-PCR) test results and symptoms changed during the menstrual cycle. The first patient developed a fever on the first day of her menstrual period, and again on the first day of her next menstrual period after hospital discharge. RT-PCR test results were positive during the first menstrual period before admission, but turned negative during hospitalization, and then were positive again during the second menstrual period after hospital discharge. Another one also developed a fever again on the first day of her menstrual period after hospital discharge. RT-PCR test results were negative before admission and during hospitalization, but turned positive during the first menstrual period after hospital discharge. The cases indicate sex hormones may play an important role in SARS-CoV-2 infection. For women with history of exposure to SARS-CoV-2, the management protocol should include assessment of the menstrual status.

Full recovery of elective orthopedic surgery in the age of COVID-19: an 8-month retrospective cohort study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to dramatic disruptions to orthopedic services. The purpose of this study is to quantify the reinstatement of elective orthopedic surgeries of our institution in Shanghai, China, and share our first-hand experiences of how this region is managing the post-outbreak period. METHODS: The number of patients receiving elective orthopedic surgeries was analyzed in the timeframe of 8 months since the start of the pandemic (from January 20 to September 16) and compared with the patients receiving the same treatment during the same period in 2019. And a detailed workflow for handling patients about to receive elective surgeries in the COVID-19 post-outbreak period was described. RESULTS: The number of the selective surgeries in the first 3 months only accounted for 31.72% of the same period in 2019 (p = 0.0031), and the ratio reached 97.47% when it came to the last 5 months (p > 0.9999). The selective surgeries even surpassed the pre-epidemic level in months 7 and 8. And the difference of the surgeries was not significant in the whole eight observed months between 2019 and 2020 (p = 0.1526). No health care providers or hospitalized patients in orthopedic departments in Shanghai have been infected nosocomially. CONCLUSIONS: Elective orthopedic surgeries have been fully recovered from the COVID-19 pandemic in our institution, and the new normalcy established during the post-outbreak period helped this region co-exist with the impact of the virus well. TRIAL REGISTRATION: Retrospectively registered, registration number: ChiCTR2000039711 , date of registration: November 6, 2020.

Herpes Zoster and Postherpetic Neuralgia in an Elderly Patient with Critical COVID-19: A Case Report.

Critical patients with COVID-19 are thought to be at high risk of developing chronic pain. However, the exact nature and mechanisms of COVID-19-related chronic pain remain largely unknown. Here, we describe clinical features, treatments and outcome of herpes zoster as well as postherpetic neuralgia in a 70-year-old woman with critical COVID-19. The patient had a history of type 2 diabetes and myasthenia gravis. She developed herpes zoster in the right 10 to 12 lumbar dermatomes in the recovery period of COVID-19. Intravenous (250 mg 3 times a day) and then oral (400 mg 5 times a day) acyclovir was used for antiviral therapy. Pregabalin (75 mg orally twice a day) and ibuprofen was used for analgesia. Her skin lesions resolved 21 days after the onset of rash. However, she continued to have persistent pain in the same dermatomal distribution. After the dosage of pregabalin was increased to 150 mg orally twice a day, her pain was partially relieved. During the telephone follow-up 4 months after herpes zoster eruption, the patient still complained intermittent pain in the right 10 to 12 lumbar dermatomes. Our case draws attention to postherpetic neuralgia in COVID-19 patients and provides a targeted suggestion for this kind of patients.

Chaos, percolation and the coronavirus spread: a two-step model.

We discuss a two-step model for the rise and decay of a new coronavirus (Severe Acute Respiratory Syndrome-CoV-2) first reported in December 2019, COVID-19. The first stage is well described by the same equation for turbulent flows, population growth and chaotic maps: a small number of infected, d 0 , grows exponentially to a saturation value, d ∞ . The typical growth time (aggressive spreading of the virus) is given by τ = 1 λ where λ is the Lyapunov exponent. After a time t crit determined by social distancing and/or other measures, the spread decreases exponentially analogous to nuclear decays and non-chaotic maps. Some countries, like China, S. Korea and Italy, are in this second stage while others including the USA are near the end of the growth stage. The model predicted 15,000 (±2250) casualties for the Lombardy region (Italy) at the end of the spreading around May 10, 2020. Without the quarantine, the casualties would have been more than 50,000, one hundred days after the start of the pandemic. The data from the 50 US states are of very poor quality because of an extremely late and confused response to the pandemic, resulting unfortunately in a large number of casualties, more than 70,000 on May 6, 2020, and more than 170,000 on August 21, 2020. S. Korea, notwithstanding the high population density ( 511 / km 2 ) and the closeness to China, responded best to the pandemic with 255 deceased as of May 6, 2020, and 301 on August 21, 2020.

Perioperative management of patients with suspected or confirmed COVID-19: review and recommendations for perioperative management from a retrospective cohort study.

BACKGROUND: Current guidelines for perioperative management of coronavirus disease 19 (COVID-19) are mainly based on extrapolated evidence or expert opinion. We aimed to systematically investigate how COVID-19 affects perioperative management and clinical outcomes, to develop evidence-based guidelines. METHODS: First, we conducted a rapid literature review in EMBASE, MEDLINE, PubMed, Scopus, and Web of Science (January 1 to July 1, 2020), using a predefined protocol. Second, we performed a retrospective cohort analysis of 166 women undergoing Caesarean section at Tongji Hospital, Wuhan during the COVID-19 pandemic. Demographic, imaging, laboratory, and clinical data were obtained from electronic medical records. RESULTS: The review identified 26 studies, mainly case reports/series. One large cohort reported greater mortality in elective surgery patients diagnosed after, rather than before surgery. Higher 30 day mortality was associated with emergency surgery, major surgery, poorer preoperative condition and surgery for malignancy. Regional anaesthesia was favoured in most studies and personal protective equipment (PPE) was generally used by healthcare workers (HCWs), but its use was poorly described for patients. In the retrospective cohort study, duration of surgery, oxygen therapy and hospital stay were longer in suspected or confirmed patients than negative patients, but there were no differences in neonatal outcomes. None of the 262 participating HCWs was infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) when using level 3 PPE perioperatively. CONCLUSIONS: When COVID-19 is suspected, testing should be considered before non-urgent surgery. Until further evidence is available, HCWs should use level 3 PPE perioperatively for suspected or confirmed patients, but research is needed on its timing and specifications. Further research must examine longer-term outcomes. CLINICAL TRIAL REGISTRATION: CRD42020182891 (PROSPERO).

[Large- scale prospective clinical study on prophylactic intervention of COVID-19 in community population using Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules].

To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.

The respiratory sound features of COVID-19 patients fill gaps between clinical data and screening methods (preprint)

Background: The 2019 novel coronavirus (COVID-19) has continuous outbreaks around the world. Lung is the main organ that be involved. There is a lack of clinical data on the respiratory sounds of COVID-19 infected pneumonia, which includes invaluable information concerning physiology and pathology. The medical resources are insufficient, which are now mainly supplied for the severe patients. The development of a convenient and effective screening method for mild or asymptomatic suspicious patients is highly demanded. Methods: This is a retrospective case series study. 10 patients with positive results of nucleic acid were enrolled in this study. Lung auscultation was performed by the same physician on admission using a hand-held portable electronic stethoscope delivered in real time via Bluetooth. The recorded audio was exported, and was analyzed by six physicians. Each physician individually described the abnormal breathing sounds that he heard. The results were analyzed in combination with clinical data. Signal analysis was used to quantitatively describe the most common abnormal respiratory sounds. Results: All patients were found abnormal breath sounds at least by 3 physicians, and one patient by all physicians. Cackles, asymmetrical vocal resonance and indistinguishable murmurs are the most common abnormal breath sounds. One asymptomatic patient was found vocal resonance, and the result was correspondence with radiographic computed tomography. Signal analysis verified the credibility of the above abnormal breath sounds. Conclusions: This study describes respiratory sounds of patients with COVID-19, which fills up for the lack of clinical data and provides a simple screening method for suspected patients.