Analysis of Factors Influencing the Corporate Performance of Listed Companies in China's Agriculture and Forestry Sector Based on a Panel Threshold Model

The global food crisis caused by COVID-19 and the Russia-Ukraine conflict have made many countries around the world realize the significance of agroforestry to a country's food security. However, China's agroforestry R&D innovation is currently lagging behind in development, and some agricultural seeds are heavily dependent on foreign countries, which seriously affects China's national food security. It is especially important to explore the reasons why China's agroforestry R&D and innovation is lagging behind. As listed agroforestry companies face the market demand directly, there is an urgent need to study the R&D innovations of listed agroforestry companies at present. This paper analyzes the impacts of R&D innovation, corporate management and supply chain management on the corporate performance of listed agroforestry companies using the entropy weighting method, GMM estimation and panel threshold model, mainly by selecting annual panel data from CSMAR for the period 2010 to 2021. The following conclusions were drawn: (1) There is a nonlinear relationship between R&D innovation and firm performance, and a 'U';-shaped relationship. This indicates that there is an entrance threshold for R&D innovation in the agroforestry industry, below which corporate performance does not improve. (2) There is a nonlinear relationship between corporate management and corporate performance, and a U-shaped relationship. (3) There is a nonlinear relationship between supply chain management and firm performance, with an inverted-U-shaped relationship. This paper explains the reasons for the slow development of R&D innovation in China's agriculture and forestry industry and fills the gap in the theoretical study of the nonlinear relationship between R&D innovation and corporate performance of listed companies in China's agriculture and forestry industry. Finally, this paper provides a theoretical basis for the decision making of government departments related to agriculture and forestry, and offers some suggestions for listed companies in agriculture and forestry to improve their corporate performance.

Assessment and prediction of the oversea imported risk of COVID-19 in Shanghai

Objective: To determine the association between global epidemic of COVID-19 and local situation of imported cases from abroad to Shanghai, and then to predict the risk of imported COVID-19 epidemic from December 2020 through March 2021.

Who and which regions are at high risk of returning to poverty during the COVID-19 pandemic?

Pandemics such as COVID-19 and their induced lockdowns/travel restrictions have a significant impact on people’s lives, especially for lower-income groups who lack savings and rely heavily on mobility to fulfill their daily needs. Taking the COVID-19 pandemic as an example, this study analysed the risk of returning to poverty for low-income households in Hubei Province in China as a result of the COVID-19 lockdown. Employing a dataset including information on 78,931 government-identified poor households, three scenarios were analysed in an attempt to identify who is at high risk of returning to poverty, where they are located, and how the various risk factors influence their potential return to poverty. The results showed that the percentage of households at high risk of returning to poverty (falling below the poverty line) increased from 5.6% to 22% due to a 3-month lockdown. This vulnerable group tended to have a single source of income, shorter working hours, and more family members. Towns at high risk (more than 2% of households returning to poverty) doubled (from 27.3% to 46.9%) and were mainly located near railway stations;an average decrease of 10–50 km in the distance to the nearest railway station increased the risk from 1.8% to 9%. These findings, which were supported by the representativeness of the sample and a variety of robustness tests, provide new information for policymakers tasked with protecting vulnerable groups at high risk of returning to poverty and alleviating the significant socio-economic consequences of future pandemics.

Combining effects of private participation and green finance for renewable energy: Growth of economy as mediating tool

As a result of the COVID-19 epidemic, a worldwide economic slump has reduced the depletion of natural resources, lowering their costs. The loss of renewable energy profitability might hinder the attainment of specified goals of sustainable development goals. By using Chinese provinces data from 1995 to 2020, this research examined the relationships between renewable energy investment (REI), green finance (GFI), growth of the economy (GDP), renewable energy production (REP), and private sector participation (PSP) in China. According to this analysis, REI, REP, and GFI are more variable throughout the given period than GDP. And PSP. A bidirectional substantial causal correlation between R.E.I. and R.E.P. was identified using the Generalized method of moments (GMM). Still, the regression coefficient between GDP and REI and REI. and GFI has a one-way causal relationship. There was no evidence that the PSP directly impacted the REI. Based on the empirical findings of this research, we propose that policies be designed to reduce volatility in REI GFI, and REP and increase support to improve sustainable economic development and environmental and renewable energy production. Examine between green financing and environmental conservation for long-term environmental quality.

The preliminary safety and immunogenicity results of a randomized, double-blind, placebo-controlled Phase I trial for a recombinant two-component subunit SARS-CoV-2 vaccine ReCOV (preprint)

Summary Background The ReCOV is a recombinant trimeric two-component SARS-CoV-2 subunit vaccine adjuvanted with BFA03. We report the preliminary safety and immunogenicity results for the ReCOV. Methods This first in human, randomized, double-blind, placebo-controlled phase I study, was conducted at 2 study sites in New Zealand. Subjects were stratified into two age cohorts (18-55 years and 56-80 years old) and then randomly assigned in a 4:1 ratio to receive two 0.5 mL intramuscular doses of the ReCOV vaccine (20µg or 40µg, adjuvanted with BFA03 in each) or placebo, 21 days apart. The primary endpoints were incidence of solicited local and systemic adverse events (AEs) and unsolicited AEs after each dose; incidence of serious adverse events (SAEs) up to 30 days after the second dose; changes in clinical laboratory tests from baseline up to 7 days after each dose; and changes in vital signs from baseline up to 30 days after the second dose. The key secondary endpoints for immunogenicity were neutralizing antibody titers against SARS-CoV-2, S1 receptor binding domain (RBD) and N-terminal domain (NTD) IgG titers post-vaccination. The T cell-specific immune response elicited by ReCOV were also evaluated. The trial was registered with ClinicalTrials.gov ( NCT04818801 ). Findings One hundred participants (50 for each age group) were randomized. The incidence of solicited local AEs in 20μg ReCOV, 40μg ReCOV, and pooled placebo group among younger adults were 60.0%, 70.0%, and 10.0%, respectively, while among older adults were 55.0%, 84.2%, and 10.0%, respectively. The incidence of solicited systemic AEs in 20μg ReCOV, 40μg ReCOV, and pooled placebo group among younger adults were 60.0%, 60.0%, and 30.0%, respectively, while among older adults were 50.0%, 52.6%, and 50.0%, respectively. All solicited AEs and unsolicited AEs were mild. No vaccination-related SAE, adverse events of special interest, and AE leading to early discontinuation were reported. ReCOV elicited SARS-CoV-2 neutralizing antibody after the first vaccination, which were increased further after the second vaccination irrespective of dose and age groups. The neutralizing antibody against wild-type SARS-CoV-2 peaked at 14 days post the second vaccination in both 20µg and 40µg ReCOV groups, with GMT of 1643.17 IU/mL and 1289.21 IU/mL among younger adults, and 1122.32 IU/mL and 680.31 IU/mL among older adults, respectively. Similarly, both anti-RBD and anti-NTD specific IgG were elicited after the first vaccination, and peaked at 14 days after the second vaccination. T helper 1 biased cellular responses were observed after ReCOV vaccinations. Interpretation Both 20 and 40µg ReCOV showed good safety profiles and elicited strong immune responses in the younger and the older adults. The results of this study support the accelerated development of ReCOV. Funding Jiangsu Recbio Technology Co., Ltd.

Using artificial intelligence technology to fight COVID-19: a review

In late December 2019, a new type of coronavirus was discovered, which was later named severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Since its discovery, the virus has spread globally, with 2,975,875 deaths as of 15 April 2021, and has had a huge impact on our health systems and economy. How to suppress the continued spread of new coronary pneumonia is the main task of many scientists and researchers. The introduction of artificial intelligence technology has provided a huge contribution to the suppression of the new coronavirus. This article discusses the main application of artificial intelligence technology in the suppression of coronavirus from three major aspects of identification, prediction, and development through a large amount of literature research, and puts forward the current main challenges and possible development directions. The results show that it is an effective measure to combine artificial intelligence technology with a variety of new technologies to predict and identify COVID-19 patients.

A trimeric NTD and RBD SARS-CoV-2 subunit vaccine induced protective immunity in CAG-hACE2 transgenic mice and rhesus macaques (preprint)

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to significant public health, economic and social problems. Development of effective vaccines is still a priority to contain the virus and end the global pandemic. In this study, we reported that ReCOV, a recombinant trimeric NTD and RBD two-component SARS-CoV-2 subunit vaccine adjuvanted with BFA03 (an AS03-like squalene adjuvant), induced high levels of neutralizing antibodies against SARS-CoV-2 and the circulating variants in mice, rabbits and rhesus macaques. Notably, two-dose immunizations of ReCOV provided complete protection against challenge with SARS-CoV-2 in hACE2 transgenic mice and rhesus macaques, without observable antibody-dependent enhancement of infection. These results support further clinical development of ReCOV and the vaccine is currently being evaluated in a phase I clinical trial in New Zealand ( NCT04818801 ).

Antigen receptor stimulation drives selection against pathogenic mtDNA variants that dysregulate lymphocyte responses (preprint)

Pathogenic mitochondrial (mt)DNA molecules can exhibit heteroplasmy in single cells and cause a range of clinical phenotypes, although their contribution to immunity is poorly understood. Here, in mice carrying heteroplasmic C5024T in mt-tRNA Ala – that impairs oxidative phosphorylation – we found a reduced mutation burden in peripheral T and B memory lymphocyte subsets, compared to their naïve counterparts. Furthermore, selection diluting the mutation was induced in vitro by triggering T and B cell antigen receptors. While C5024T dysregulated naïve CD8 + T cell respiration and metabolic remodeling post-activation, these phenotypes were partially ameliorated by selection. Analogous to mice, peripheral blood memory T and B lymphocyte subsets from human MELAS (Mitochondrial Encephalomyopathy with Lactic Acidosis and Stroke-like episodes) patients – carrying heteroplasmic A3243G in mt-tRNA Leu – displayed a reduced mutation burden, compared to naïve cells. In both humans and mice, mtDNA selection was observed in IgG + antigen-specific B cells after SARS-CoV-2 Spike vaccination, illustrating an on-going process in vivo . Taken together, these data illustrate purifying selection of pathogenic mtDNA variants during the oxidative phosphorylation checkpoints of the naïve-memory lymphocyte transition. Highlights In human MELAS patients (A3243G in mt-tRNA Leu ) and a related mouse model (C5024T in mt-tRNA Ala ), T and B memory subsets displayed a reduced mtDNA mutation burden compared to their naïve counterparts. Selection was observed in antigen-specific IgG + B cells after SARS-CoV-2 Spike protein vaccination. T and B cell antigen receptor stimulation triggered purifying selection in vitro , facilitating mechanistic studies of mtDNA selection. Heteroplasmic pathogenic mutations in mtDNA dysregulated metabolic remodeling after lymphocyte activation and reduced macrophage OXPHOS capacity.

Integrated Analysis of microRNAs and Metabolomics in Rat’s Serum Reveals Multi-action Modes of Qingfei Paidu Decoction for COVID-19 Treatment (preprint)

Background: During the fight against coronavirus disease 2019 (COVID-19) in China, Qingfei Paidu decoction (QFPDD) has been widely applied to treat COVID-19 patients. Retrospective studies showed that QFPDD could improve clinical outcomes of COVID-19. Thus, it is necessary and interesting to explore the action mode of QFPDD for further application and development. Methods: Sprague-Dawley (SD) rats were randomly divided into two groups, QFPDD (n=9) and control (n=10) groups. They were parallelly treated for 12 days with QFPDD and warm distilled water, respectively. At the endpoint, the microRNA (miRNA or miR) profiles in serum were detected to identify differently expressed miRNAs (DEMs). Then, the action mode of QFPDD were explored via review of potential roles of DEMs and functional enrichment analysis of their targets (e.g., GO enrichment and KEGG pathway analysis), especially focusing on the aspects of immunity, inflammation, virus infection and pulmonary fibrosis. Core genes were identified based on KEGG pathway analysis. Metabolomics were detected in serum and significantly changed metabolites (SCMs), especially the metabolic substrates and products of enzyme of core gene were identified as biomarkers to validate the regulation of DEMs to enzyme activity of core gene through metabolomic analysis and linear correlation analysis between SCMs and DEMs. Results: 23 DEMs were identified in the serum between QFPDD and control groups, with 1636 predicted genes. Reported evidence has showed that both the DEMs and their target genes involve regulation of immunity, inflammation, virus infection and pulmonary fibrosis. Phospholipase C, gamma 1 (Plcg1) was identified as a core gene and predicted to be upregulated attributed to downregulation of novel-89-mature. The levels of three SCMs, PC(P-18:1(11Z)/22:5(4Z,7Z,10Z,13Z,16Z)), PC(22:5(4Z,7Z,10Z,13Z,16Z)/P-18:0) and PC(16:1(9Z)/16:1(9Z)), which were the metabolic substrates of phospholipase C, were significantly reduced in QFPDD group, in addition, PC(P-18:1(11Z)/22:5(4Z,7Z,10Z,13Z,16Z)) and PC(22:5(4Z,7Z,10Z,13Z,16Z)/P-18:0) presented positively linear correlation with the expression level of novel-89-mature. The level of phosphorylcholine, a product of PCs metabolized by phospholipase C, was significantly elevated in QFPDD group. Conclusion: QFPDD can induce modification of miRNAs profile, and subsequently multi-regulate the immunity, inflammation, virus infection and pulmonary fibrosis in vivo, playing an important role for the positive outcomes of COVID-19 patients treated by QFPDD in China.

Epidemiology Characteristic and Co-infection Pattern of Pathogens in Patients With Respiratory Tract Infection in Southern China, 2018-2020. (preprint)

Background: Respiratory tract infections (RTIs) is the highest prevalent disease and southern china has a wide spectrum of respiratory pathogen. The aim of this work was to renew the epidemiology characteristics of respiratory pathogens found in children and adults with RTIs from 2018 to 2020 in southern China. Methods: In this work, a total of 134,552 nasopharyngeal or throat swabs (patients from 407 hospitals) were analyzed, and fourteen respiratory viruses (Influenza A virus, influenza B virus, parainfluenza viruses, respiratory syncytial virus, adenovirus, human rhinovirus, human metapneumovirus, human Coronavirus, human bocavirus, enterovirus, cytomegalovirus, herpes simplex virus, mycoplasma pneumoniae and chlamydia pneumoniae) were detected using PCR/RT-PCR. Result: The most common respiratory pathogens in southern china were ADV (16.19%), RSV (15.48%), RHV (11.51%), IAV (10.93%), MP (8.95%), EBV (8.70%), PIV (7.67%), IBV (5.44%), with IAV and ADV as the most prevalent pathogens in adults (11.68%) and children (17.10%) respectively. In detail, ADV (16.30%) and RSV (18.93%) are most common in 0-4 years old, with IAV (16.68%), ADV (20.36%) in 5-14 years old, with EBV (7.48%, 8.74%), IAV (15.43, 9.76%) in 15-49y, 50-64y and IAV (7.37%), IBV (2.43%) in 65-105y. Over three years witnessed an increase in PDR of PIV in 0-4y, 5-14y and 65-105y, and RHV in 5-14y and 15-49y. In month distribution, the positive detection rate of pathogens in adults were generally lower than that in children except for EBV and majority of pathogens has shown a sharp decline in 2020. In Upper RTIs, 77.27% (17/ 22) of co-infected patients had infection to ADV, with poly-infection to ADV and RHV the highest (8/22). In Lower RTIs, the ADV infected patients showed that its co-infection rate to MP, PIV, RHV or RSV were 19.51% (48/246), 15.45% (38/246), 14.63% (36/246) and 14.63% (36/246) respectively. Only IAV, IBV and EBV were detected in co-infection patients with lower RTIs. Conclusion: IAV and ADV were the most important respiratory pathogen in adults and children respectively in southern Chin and cross-reactivity might exist between ADV, RHV, PIV and MP. These should be taken into consideration when they formulate the strategies for co-infection avoidance in patients.

A case report of human immunodeficiency virus combined with SARS-CoV-2 infection

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease caused by a novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) infection, and its spread speed Fast, the crowd is generally susceptible [1]. AIDS (acquired immune deficiency syndrome, AIDS) is caused by human immunodeficiency virus (human immunodeficiency virus).

Identification of four linear B-cell epitopes on the SARS-CoV-2 spike protein able to elicit neutralizing antibodiesIdentification of four linear B-cell epitopes on the SARS-CoV-2 spike protein able to elicit neutralizing antibodies (preprint)

SARS-CoV-2 unprecedentedly threatens the public health at worldwide level. There is an urgent need to develop an effective vaccine within a highly accelerated time. Here, we present the most comprehensive S-protein-based linear B-cell epitope candidate list by combining epitopes predicted by eight widely-used immune-informatics methods with the epitopes curated from literature published between Feb 6, 2020 and July 10, 2020. We find four top prioritized linear B-cell epitopes in the hotspot regions of S protein can specifically bind with pooled serum antibodies from horses, mice, and monkeys inoculated with different SARS-CoV-2 vaccine candidates or five patients recovering from COVID-19. The four linear B-cell epitopes can induce neutralizing antibodies against both pseudo and live SARS-CoV-2 virus in immunized wild-type BALB/c mice. This study suggests that the four linear B-cell epitopes are potentially important candidates for serological assay or vaccine development.

Antibody response among COVID-19 patient with and without re-detectable positive RT-PCR results in convalescent phases (preprint)

Objective: To analyze the dynamic of total, IgA, IgM and IgG antibody of the confirmed COVID-19 patients during convalescent phases to understand the kinetics of antibody response among recovered patients.Methods: From March 4 to April 29, 2020, a total of 143 recovered COVID-19 patients with clear date of illness onset available were enrolled in this study. Nasopharyngeal and anal swabs were collected for SARS-CoV-2 RNA testing. Blood samples were collected for antibodies testing. Results: A total of 275 blood samples up to 96 days after illness onset were collected from 143 recovered patients. High titers of total and IgG antibodies continued to persist for over 3 months, with 100% and 99.3% patients remaining positive for total and IgG antibody. IgM antibody declined rapidly with a median time to seronegative at 67 (95%CI: 59, 75) days after illness onset. Around 25% patients were seronegative for IgA antibody at month 3 after illness onset. No statistical significance difference was founded in the antibody kinetics between patients with and without re-detectable positive RT-PCR results during in convalescent phases. Conclusion: Similar high antibody titers of total and IgG antibody continued to persist for over 3 months among recovered COVID-19 patients with and without re-detectable positive RT-PCR results.

Special strategies and management of urological diseases during the COVID-19 Pandemic: initial experiences from a Medical Center of China

ABSTRACT Although urological diseases are not directly related to coronavirus disease 2019 (COVID-19), urologists need to make comprehensive plans for this disease. Urological conditions such as benign prostatic hyperplasia and tumors are very common in elderly patients. This group of patients is often accompanied by underlying comorbidities or immune dysfunction. They are at higher risk of COVID-19 infection and they tend to have severe manifestations. Although fever can occur along with urological infections, it is actually one of the commonest symptoms of COVID-19;urologists must always maintain a high index of suspicion in their clinical practices. As a urological surgeon, how we can protect medical staff during surgery is a major concern. Our hospital had early adoption of a series of strict protective and control measures, and was able to avoid cross-infection and outbreak of COVID-19. This paper discusses the effective measures that can be useful when dealing with urological patients with COVID-19.

Identification of four linear B-cell epitopes on the SARS-CoV-2 spike protein able to elicit neutralizing antibodies (preprint)

SARS-CoV-2 unprecedentedly threatens the public health at worldwide level. There is an urgent need to develop an effective vaccine within a highly accelerated time. Here, we present the most comprehensive S-protein-based linear B-cell epitope candidate list by combining epitopes predicted by eight widely-used immune-informatics methods with the epitopes curated from literature published between Feb 6, 2020 and July 10, 2020. We find four top prioritized linear B-cell epitopes in the hotspot regions of S protein can specifically bind with serum antibodies from horse, mouse, and monkey inoculated with different SARS-CoV-2 vaccine candidates or a patient recovering from COVID-19. The four linear B-cell epitopes can induce neutralizing antibodies against both pseudo and live SARS-CoV-2 virus in immunized wild-type BALB/c mice. This study suggests that the four linear B-cell epitopes are potentially important candidates for serological assay or vaccine development.

The MERS-CoV receptor gene is among COVID-19 risk factors inherited from Neandertals (preprint)

In the current SARS-CoV-2 pandemic, two genetic regions derived from Neandertals have been shown to increase and decrease, respectively, the risk of falling severely ill upon infection. Here, we show that 2-8% of people in Eurasia carry a variant promoter region of the DPP4 gene inherited from Neandertals. This gene encodes an enzyme that serves as a receptor for the coronavirus MERS-CoV and is currently not believed to be a receptor for SARS-CoV-2. However, the Neandertal DPP4 variant doubles the risk to become critically ill in COVID-19.

Millisecond-scale molecular dynamics simulation of spike RBD structure reveals evolutionary adaption of SARS-CoV-2 to stably bind ACE2 (preprint)

The Receptor Binding Domain (RBD) of the SARS-CoV-2 surface spike (S) protein interacts with host angiotensin converting enzyme 2 (ACE2) to gain entry to host cells and initiate infection1-3. Detailed, accurate understanding of key interactions between S RBD and ACE2 provides critical information that may be leveraged in the development of strategies for the prevention and treatment of COVID-19. Utilizing the published sequences and cryo-EM structures of both the viral S RBD and ACE24,5, we performed in silico molecular dynamics (MD) simulations of free S RBD and of its interaction with ACE2 over the exceptionally long durations of 2.9 and 2 milliseconds, respectively, to elucidate the nature and relative affinity of S RBD surface residues for the ACE2 binding region. Our findings reveal that free S RBD has assumed an optimized ACE2 binding-ready conformation, incurring little entropic penalty for binding, an evolutionary adaptation that contributes to its high affinity for the receptor6. We further identified high probability molecular binding interactions that inform both vaccine design and therapeutic development, which may include recombinant ACE2-based spike decoys7 and/or allosteric S RBD-ACE2 binding inhibitors8,9 to prevent or arrest infection and thus disease.