The optimisation of public health emergency governance: a simulation study based on COVID-19 pandemic control policy.

BACKGROUND: The outbreak of the COVID-19 pandemic sparked numerous studies on policy options for managing public health emergencies, especially regarding how to choose the intensity of prevention and control to maintain a balance between economic development and disease prevention. METHODS: We constructed a cost-benefit model of COVID-19 pandemic prevention and control policies based on an epidemic transmission model. On this basis, numerical simulations were performed for different economies to analyse the dynamic evolution of prevention and control policies. These economies include areas with high control costs, as seen in high-income economies, and areas with relatively low control costs, exhibited in upper-middle-income economies. RESULTS: The simulation results indicate that, at the outset of the COVID-19 pandemic, both high-and low-cost economies tended to enforce intensive interventions. However, as the virus evolved, particularly in circumstances with relatively rates of reproduction, short incubation periods, short spans of infection and low mortality rates, high-cost economies became inclined to ease restrictions, while low-cost economies took the opposite approach. However, the consideration of additional costs incurred by the non-infected population means that a low-cost economy is likely to lift restrictions as well. CONCLUSIONS: This study concludes that variations in prevention and control policies among nations with varying income levels stem from variances in virus transmission characteristics, economic development, and control costs. This study can help researchers and policymakers better understand the differences in policy choice among various economies as well as the changing trends of dynamic policy choices, thus providing a certain reference value for the policy direction of global public health emergencies.

Digital Health Literacy: Bibliometric Analysis.

BACKGROUND: Digital health is growing at a rapid pace, and digital health literacy has attracted increasing attention from the academic community. OBJECTIVE: The purposes of this study are to conduct a systematic bibliometric analysis on the field of digital health literacy and to understand the research context and trends in this field. METHODS: Methods: A total of 1955 scientific publications were collected from the Web of Science core collection. Institutional co-operation, journal co-citation, theme bursting, keyword co-occurrence, author co-operation, author co-citation, literature co-citation, and references in the field of digital health literacy were analyzed using the VOSviewer and CiteSpace knowledge mapping tools. RESULTS: The results demonstrate that the United States has the highest number of publications and citations in this field. The University of California System was first in terms of institutional contributions. The Journal of Medical Internet Research led in the number of publications, citations, and co-citations. Research areas of highly cited articles in the field of digital health literacy mainly include the definition and scale of health literacy, health literacy and health outcomes, health literacy and the digital divide, and the influencing factors of health literacy. CONCLUSIONS: We summarized research progress in the field of digital health literacy and reveal the context, trends, and trending topics of digital health literacy research through statistical analysis and network visualization. We found that digital health literacy has a significant potential to improve health outcomes, bridge the digital divide, and reduce health inequalities. Our work can serve as a fundamental reference and directional guide for future research in this field.

Toxicity of the microcystin-producing cyanobacteria Microcystis aeruginosa to shrimp Litopenaeus vannamei.

Microcystis aeruginosa is reported to cause cyanobacterial blooms in shrimp breeding ponds, which can result in significant shrimp mortality. However, the toxic effects of M. aeruginosa on Litopenaeus vannamei are still not completely understood. In this paper, the toxicity of M. aeruginosa cells to L. vannamei was examined, and the toxic components in the cells were analyzed through high-pressure liquid chromatography (HLPC). In addition, the immune response of shrimp to the M. aeruginosa cell extract was assessed by measuring the activity of immune-related enzymes, as well as the transcription of the relevant genes. The results showed that M. aeruginosa cells, extract and cell-free cultured medium resulted in a 100%, 98.3%, and 1.7% mortality rate in shrimp, respectively. HPLC analysis results revealed the presence of microcystin-LR (MC-LR) at a concentration of 190.40 mg/kg of cells. In addition, the activity and gene transcription of two immune related enzymes, SOD and LZM, were both significantly reduced in shrimp hepatopancreas (p < 0.05) after injection with extract. However, reduced glutathione (GSH) content was slightly increased, but the ratio of GSH to GSSG decreased. The transcription of gst gene function as detoxification, was significantly downregulated (p < 0.05). The results demonstrated that M. aeruginosa cell extract was highly toxic to L. vannamei, and exerted a negative effect on shrimp immunity including reduction of antioxidant capacity, antibacterial activity and detoxification activity, due to toxins including microcystin-LR.

Effect of guava leaves on growth and the non-specific immune response of Penaeus monodon.

Guava (Psidium guajava L.) leaf extracts have antiviral and antibacterial activity against shrimp pathogens such as yellow-head virus (YHV), white spot syndrome virus (WSSV), and Vibrio harveyi, which make it a potential water disinfectant for use in shrimp culture. In this study, the safety of guava leaf supplementation in shrimp was evaluated by studying its influence on growth and the non-specific immune response of Penaeus monodon. Six diets containing different levels of guava leaves (0% [basal diet], 0.025% [G1], 0.05% [G2], 0.1% [G3], 0.2% [G4], and 0.4% [G5]) were fed to groups of shrimp (1.576 ± 0.011 g body weight) in triplicate for 56 days. Growth performance (final body weight, WG, PWG, SGR) of shrimp fed guava leaf diets was significantly higher (P < 0.05) than that of shrimp fed on the basal diet. The G1 diet resulted in the highest body weight gain (308.44%), followed by the G2 (295.45%), G3 (283.05%), G5 (281.29%), G4 (276.11%), and finally the basal diet (214.58%). Survival of shrimp in the G1 diet group was higher than that of shrimp in the control and the other experimental groups; however, no statistical differences (P > 0.05) were found. Dietary supplementation with guava leaf improved the activities of prophenoloxidase (PO) and nitric oxide synthase (NOS) in serum, and of superoxide dismutase (SOD), acid phosphatase (ACP), alkaline phosphatase (AKP), and lysozyme (LSZ) both in serum and hepatopancreas of shrimp. In the experimental groups, the activities of these enzymes followed a similar pattern of change; they increased initially at low levels of dietary supplementation and then decreased with increasing concentrations of dietary guava leaf. Serum PO and SOD activities in shrimp fed the G1 diet reached 7.50 U ml(-1) and 178.33 U ml(-1), respectively, with PO activity being significantly higher than in controls. In shrimp fed the G1 diet, SOD, ACP, and AKP activities in hepatopancreas were significantly higher than in the controls, reaching 57.32 U g(-1), 23.28 U g(-1), and 19.35 U g(-1) protein, respectively. The highest activities of serum ACP, AKP, LSZ, and of hepatopancreas LSZ, were observed in the G3 diet group. Total nitric oxide synthase (TNOS) activity was highest (64.80 U ml(-1)) in the G4 diet group, which was significantly higher than that observed in the control group. These results suggest that dietary guava leaf supplementation could enhance the growth performance and non-specific immune response of P. monodon. Therefore, guava leaf is considered safe for use as a water disinfectant in shrimp culture.

Analyzing big data with the hybrid interval regression methods.

Big data is a new trend at present, forcing the significant impacts on information technologies. In big data applications, one of the most concerned issues is dealing with large-scale data sets that often require computation resources provided by public cloud services. How to analyze big data efficiently becomes a big challenge. In this paper, we collaborate interval regression with the smooth support vector machine (SSVM) to analyze big data. Recently, the smooth support vector machine (SSVM) was proposed as an alternative of the standard SVM that has been proved more efficient than the traditional SVM in processing large-scale data. In addition the soft margin method is proposed to modify the excursion of separation margin and to be effective in the gray zone that the distribution of data becomes hard to be described and the separation margin between classes.

Removal of nitrogen from secondary effluent of a petrochemical industrial park by a hybrid biofilm-carrier reactor with one-stage ANAMMOX.

A laboratory study was undertaken to explore the capability of one-stage ANAMMOX in a hybrid biofilm-carrier reactor (HBCR) fed with petrochemical wastewater. Under favorable operating conditions in continuous-flow operations (at the dissolved oxygen level of 0.5-1.0 mg L(-1)), the average total nitrogen (TN) removal efficiency reached 62-67% and approximately 90% of TN can be removed by ANAMMOX. In batch operations of the hybrid biofilm-carrier reactor (without adding carbon substrate), the specific TN removal rate of the reactor in which both Kaldnes and nonwoven carriers were kept was two-fold higher than that of the reactor in which only nonwoven carriers were kept. This indicated that the microbial activity of thinner biofilms (Kaldnes carriers) was remarkably higher than that of thicker biofilms (nonwoven carriers). Finally, based on the 16S rRNA clone library, a cluster of ANAMMOX Candidatus Kuenenia stuttgartiensis was identified.

Determinants of and Willingness to Use and Pay for Digital Health Technologies Among the Urban Elderly in Hangzhou, China.

Purpose: In recent years, little research has been conducted on the willingness to use and pay for digital health technologies for elderly people. Thus, this study investigates the willingness to use and pay for digital health technologies and their influential factors among urban elderly in Hangzhou, China. Methods: A structured questionnaire was completed by 639 older adults from 12 communities in Hangzhou. This paper presents a descriptive statistics analysis and performs a multivariate regression to identify the determinants of willingness to use and pay for digital health technologies among the elderly. Results: The result shows the percentage of participants who chose very willing (3.6%) and partly willing (10%) to use was lower than those who were less unwilling (26.4%) and not willing (27.1%) to use. The percentage of participants who are unwilling (less unwilling,30.5%; not willing, 39.7%) to pay for digital health technology is even higher. The regression results show that age, working status, exercise and physical activity, medical insurance, income, life satisfaction and history of illness were significantly associated with willingness to use digital health technology among urban elderly. On the other hand, age, exercise status, income and history of illness were significantly associated with willingness to pay for digital health technologies among older adults. Conclusion: The overall willingness to use and pay for digital health technologies are low among urban older people living in Hangzhou. Our results have important implications for digital health policy making. Practitioner and regulator should develop strategies to improve the supply of digital health technology services to meet different demands of the elderly with different age, working status, exercise and physical activity, medical insurance, income, life satisfaction and history of illness. And medical insurance would be an important instrument to facilitate digital health development.

The Public Health Governance of the COVID-19 Pandemic: A Bibliometric Analysis.

The 2019 global outbreak of COVID-19 has had a huge impact on public health governance systems around the world. In response, numerous scholars have conducted research on public health governance in the context of the COVID-19 pandemic. This paper provides a bibliometric analysis of 1437 documents retrieved from the Web of Science (WoS) core collection database, with 49,695 references. It analyses the research directions, countries of publications, core journals, leading authors and institutions and important publications. The paper also summarises research trends by analysing the co-occurrence of keywords, frequently cited documents and co-cited references. It summarises the global responses to COVID-19, including public health interventions and a range of supporting policies based on the features and impacts of the COVID-19 pandemic. The paper provides comprehensive literary support and clear lines of research for future studies on the governance or regulation of public health emergencies.

Research on Health Disparities Related to the COVID-19 Pandemic: A Bibliometric Analysis.

With the outbreak of the 2019 coronavirus (COVID-19) pandemic, the issue of increasing health disparities has received a great deal of attention from scholars and organizations. This study analyzes 2282 papers on COVID-19-related health disparities that have been retrieved from the WOS database, with 58,413 references. Using bibliometric analysis and knowledge mapping visualizations, the paper focuses on the academic structure and research trends by examining the research distribution of countries, journals and authors, keywords, highly cited articles, and reference co-citation. The results show that the United States has contributed the most, and the International Journal of Environmental Research and Public Health has published the largest number of papers on this topic. As for the core authors, Michael Marmot is the most productive. Issues such as racial health, mental health, and digital health disparities have been the trending topics of the COVID-19-related health disparities. The research directions include the features, factors, and interventions of health disparities under the influence of COVID-19. As such, this study provides literature support and suggestions to investigate COVID-19-related health disparities. The findings of the paper also remind public health regulators to consider factors of health disparities when developing long-term public health regulatory policies related to the pandemic.

Molecular cloning and expression analysis of a F-type lectin gene from Japanese sea perch (Lateolabrax japonicus).

The techniques of homology cloning and anchored PCR were used to clone the fucose-binding lectin (F-type lectin) gene from Japanese sea perch (Lateolabrax Japonicus). The full-length cDNA of sea perch F-lectin (JspFL) contained a 5' untranslated region (UTR) of 39 bp, an ORF of 933 bp encoding a polypeptide of 310 amino acids with an estimated molecular mass of 10.82 kDa and a 3' UTR of 332 bp. The searches for nucleotides and protein sequence similarities with BLAST analysis indicated that the deduced amino acid sequence of JspFL was homological to the Fucose-binding lectin in other fish species. In the JspFL deduced amino acid sequence, two tandem domains that exhibit the eel carbohydrate-recognition sequence motif were found. The temporal expressions of gene in the different tissues were measured by real-time PCR. And the mRNA expressions of the gene were constitutively expressed in tissues including spleen, head-kidney, liver, gill, and heart. The JspFL expression in spleen was different during the stimulated time point, 2 h later the expression level became up-regulated, and 6 h later the expression level became down-regulated. The result indicated that JspFL was constitutive and inducible expressed and could play a critical role in the host-pathogen interaction.

Molecular cloning and mRNA expression analysis of interleukin-8 gene in Japanese sea perch (Lateolabrax japonicus).

Interleukin-8 (IL-8), the first known chemokine, is a CXC chemokine, which is cable of attracting neutrophils and inducing them to release lysozomal enzymes, triggering the respiratory burst. In the present study, the cDNA of an IL-8 was cloned from Japanese sea perch Lateolabrax japonicus (designated LjIL-8) by homology cloning and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of LjIL-8 consisted of 803 nucleotides with a canonical polyadenylation signal sequence AATAAA and a poly(A) tail, and an open reading frame (ORF) of 300 bp encoding a polypeptide of 99 amino acid residues with a predicted molecular weight of 6.6 kDa. The high identity of LjIL-8 with IL-8 in other organisms indicated that LjIL-8 should be a new member of the IL-8 family. By fluorescent quantitative real-time PCR, mRNA transcript of LjIL-8 was detectable in all the examined tissues with higher level in spleen and head-kidney. The temporal expression of LjIL-8 mRNA in the spleen was up-regulated by lipopolyssacharide (LPS) stimulation and reached the maximum level at 6 h post-stimulation, and then dropped back to the original level gradually. These results indicated that LjIL-8 was a constitutive and inducible acute-phase protein that perhaps involved in the immune defense of L. japonicus.

Molecular cloning and mRNA expression of cathepsin C gene in black tiger shrimp (Penaeus monodon).

Cathepsin C (dipeptidyl-peptidase I, DPPI) is a lysosomal cysteine proteinase belonging to the papain superfamily, which is capable of removing dipeptides sequentially from the amino terminus of peptide and protein substrates. In the present study, the cDNA of a cathepsin C was cloned from black tiger shrimp Penaeus monodon (designated PmcathepsinC) by homology cloning and rapid amplification of cDNA ends (RACE) approaches. The full-length cDNA of PmcathepsinC consisted of 2051 nucleotides with a canonical polyadenylation signal sequence AATAAA and a poly(A) tail, and an open reading frame (ORF) of 1350 bp encoding a polypeptide of 449 amino acid residues with a predicted molecular weight of 50.0 kDa and theoretical isoelectric point of 5.65. The high identity of PmcathepsinC with Cathepsin C in other organisms indicated that PmcathepsinC should be a new member of the Cathepsin C family. By fluorescent quantitative real-time PCR, mRNA transcript of PmcathepsinC was detectable in all the examined tissues with higher level in ovary and heart. The temporal expression of PmcathepsinC mRNA in the hepatopancreas was up-regulated by lipopolysaccharide (LPS) stimulation and reached the maximum level at 4 h post-stimulation, and then dropped back to the original level gradually. These results indicated that PmcathepsinC was a constitutive and inducible acute-phase protein that perhaps involved in the immune defense of P. monodon.

Persistence and spatial variation of antibiotic resistance genes and bacterial populations change in reared shrimp in South China.

More attention has been paid to the abundance and diversity of antibiotic resistance genes (ARGs) in aquatic environments. However, few studies have investigated the persistence and spatial variation of ARGs in aquatic organisms. This study investigated the occurrence and abundance of ARGs and the bacterial populations in shrimp intestinal tracts during the rearing period in different regions of Guangdong, South China. The results showed that sul1, sul2, qnrD, and floR were the predominant ARGs. Compared with those of juvenile shrimp, the total concentrations of ARGs in the intestinal tract of adult shrimp in three shrimp farms were 2.45-3.92 times higher (p < 0.05), and the bacterial populations in the adult shrimp intestinal tract changed considerably. Redundancy analysis (RDA) showed that the abundance of Proteobacteria, Firmicutes, and Verrucomicrobia in Farms A, B, and C, respectively, were strongly positively correlated with the most abundant and predominant genes (sul1 and qnrD for Farm A; floR and sul2 for Farm B; floR and sul2 for Farm C) in the shrimp intestinal tract. The results of this study indicated that ARGs gained persistence in the developmental stages of the reared shrimp. Different phyla of predominant bacteria were responsible for the increase of ARGs abundance in the shrimp intestinal tract in different regions. This study represents a case study of the persistence and spatial variation of ARGs in aquaculture and can be a reference for the determination of harmful impacts of ARGs on food safety and human health.

Molecular cloning, expression and functional analysis of three subunits of protein phosphatase 2A (PP2A) from black tiger shrimps (Penaeus monodon).

Protein phosphatase 2A (PP2A) is a cellular serine-threonine (Ser/Thr) phosphatase that plays a crucial role in regulating most cellular functions. In the present study, the full-length cDNAs of three subunits of PmPP2A (PmPP2A-A, PP2A-B and PP2A-C) were cloned from Penaeus monodon, which are the first available for shrimps. Sequence analysis showed that PmPP2A-A, PmPP2A-B and PmPP2A-C encoded polypeptides of 591, 443, and 324 amino acids, respectively. The mRNAs of three subunits of PmPP2A were expressed constitutively in all tissues examined, and predominantly in the ovaries. In ovarian maturation stages, the three subunits of PmPP2A were continuously but differentially expressed. Dopamine and 5-hydroxytryptamine injection experiments were conducted to study the expression profile of three subunits of PmPP2A, and the results indicated that PmPP2A played a negative regulatory role in the process of ovarian maturation. In addition, the recombinant proteins of three subunits of PmPP2A were successfully obtained, and the phosphatase activity of PmPP2A was tested in vitro. The results of this study will advance our understanding about the molecular mechanisms of PmPP2A in Penaeus monodon.

Molecular cloning and expression analysis of a heat shock protein (Hsp90) gene from black tiger shrimp (Penaeus monodon).

The techniques of homology cloning and anchored PCR were used to clone the Hsp90 gene from black tiger shrimp. The full length cDNA of black tiger shrimp Hsp90 (btsHsp90) contained a 5' untranslated region (UTR) of 72 bp, an ORF (open reading frame) of 2160 bp encoding a polypeptide of 720 amino acids with an estimated molecular mass of 83-kDa and a 3' UTR of 288 bp. The sequence of the coding region showed 90 and 84% homology with that of the Chiromantes haematocheir and Homo sapiens, respectively. Conserved signature sequences of Hsp90 gene family were found in the btsHsp90 deduced amino acid sequence. The temporal expressions of Hsp90 gene were constitutively in the black tiger shrimp tissues including liver, ovary, muscle, brain stomach, and heart, and their levels were markedly enhanced after 30-min heat treatment at 37 degrees C. In ovarian maturation stages, the expression of btsHsp90 was strongest in the second stage, weaker in the fourth and first stage.