Accurate quantification of DNA using on-site PCR (osPCR) by characterizing DNA amplification at single-molecule resolution.

Despite the need in various applications, accurate quantification of nucleic acids still remains a challenge. The widely-used qPCR has reduced accuracy at ultralow template concentration and is susceptible to nonspecific amplifications. The more recently developed dPCR is costly and cannot handle high-concentration samples. We combine the strengths of qPCR and dPCR by performing PCR in silicon-based microfluidic chips and demonstrate high quantification accuracy in a large concentration range. Importantly, at low template concentration, we observe on-site PCR (osPCR), where only certain sites of the channel show amplification. The sites have almost identical ct values, showing osPCR is a quasi-single molecule phenomenon. Using osPCR, we can measure both the ct values and the absolute concentration of templates in the same reaction. Additionally, osPCR enables identification of each template molecule, allowing removal of nonspecific amplification during quantification and greatly improving quantification accuracy. We develop sectioning algorithm that improves the signal amplitude and demonstrate improved detection of COVID in patient samples.

Hematological characteristics of COVID-19 patients with fever infected by the Omicron variant in Shanghai: A retrospective cohort study in China.

BACKGROUND: A wave of the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has rapidly spread in Shanghai, China. Hematological abnormalities have been reported in coronavirus disease 2019 (COVID-19) patients; however, the difference in hematological parameters between COVID-19 patients with fever and patients who are febrile from other causes remains unexplored. METHODS: This retrospective cohort study enrolled 663 SARS-CoV-2 positive patients identified by RT-PCR. Clinical parameters, including age, sex, and threshold cycle values of all COVID-19 patients, and hematological parameters of COVID-19 patients in the fever clinic were abstracted for analysis. RESULTS: Overall, 60.8% of COVID-19 patients were male, and the median age was 45 years. Most of COVID-19 patients were asymptomatic, while 25.8% of patients showed fever and 10.9% of patients had other emergencies. COVID-19 patients with fever had significantly lower white blood cells (WBCs), neutrophils, lymphocytes, platelets and C-reactive protein (CRP), and significantly higher monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume (MPV), and mean platelet volume-to-platelet ratio (MPR) levels, compared with those in SARS-CoV-2 negative patients with fever from other causes (p < 0.05). Neutrophil-to-lymphocyte ratio (NLR), PLR, and systemic inflammatory index (SII) levels were significantly higher in COVID-19 patients with emergencies (p < 0.05). WBCs showed the best performance with an area under the curve (0.756), followed by neutrophils (0.730) and lymphocytes (0.694) in the diagnosis of COVID-19 in the fever clinic. CONCLUSION: WBCs, neutrophils, lymphocytes, platelets, CRP and MLR, PLR, and MPR may be useful in early diagnosis of COVID-19 in the fever clinic.

Ultraefficiently Calming Cytokine Storm Using Ti3C2T x MXene.

During the global outbreak of COVID-19 pandemic, "cytokine storm" conditions are regarded as the fatal step resulting in most mortality. Hemoperfusion is widely used to remove cytokines from the blood of severely ill patients to prevent uncontrolled inflammation induced by a cytokine storm. This article discoveres, for the first time, that 2D Ti3C2T x MXene sheet demonstrates an ultrahigh removal capability for typical cytokine interleukin-6. In particular, MXene shows a 13.4 times higher removal efficiency over traditional activated carbon absorbents. Molecular-level investigations reveal that MXene exhibits a strong chemisorption mechanism for immobilizing cytokine interleukin-6 molecules, which is different from activated carbon absorbents. MXene sheet also demonstrates excellent blood compatibility without any deleterious side influence on the composition of human blood. This work can open a new avenue to use MXene sheets as an ultraefficient hemoperfusion absorbent to eliminate the cytokine storm syndrome in treatment of severe COVID-19 patients.

Epidemiological analysis of Group A streptococcus infection diseases among children in Beijing, China under COVID-19 pandemic

Background Group A streptococcus is human-restricted gram-positive pathogen, responsible for various clinical presentations from mild epidermis infections to life threatened invasive diseases. Under COVID-19 pandemic,. the characteristics of the epidemic strains of GAS could be different. Purpose To investigate epidemiological and molecular features of isolates from GAS infections among children in Beijing, China between January 2020 and December 2021. Antimicrobial susceptibility profiling was performed based on Cinical Laboratory Sandards Institute. Distribution of macrolide-resistance genes, emm types, and superantigens was examined by polymerase chain reaction. Results 114 GAS isolates were collected which were frequent resistance against erythromycin (94.74%), followed by clindamycin (92.98%), tetracycline (87.72%). Emm12 (46.49%), emm1 (25.44%) were dominant emm types. Distribution of ermB, ermA, and mefA gene was 93.85%, 2.63%, and 14.04%, respectively. Frequent superantigenes identified were smeZ (97.39%), speG (95.65%), and speC (92.17%). Emm1 strains possessed smeZ, ssa, and speC, while emm12 possessed smeZ, ssa, speG, and speC. Erythromycin resistance was predominantly mediated by ermB. Scarlet fever strains harbored smeZ (98.81%), speC (94.05%). Impetigo strains harbored smeZ (88.98%), ssa (88.89%), and speC (88.89%). Psoriasis strains harbored smeZ (100%). Conclusions Under COVID-19 pandemic, our collections of GAS infection cutaneous diseases decreased dramatically. Epidemiological analysis of GAS infections among children during COVID-19 pandemic was not significantly different from our previous study. There was a correlation among emm, superantigen gene and disease manifestations. Long-term surveillance and investigation of emm types and superantigens of GAS prevalence are imperative.

Epidemiological analysis of Group A streptococcus infection diseases among children in Beijing, China under COVID-19 pandemic.

BACKGROUND: Group A streptococcus is human-restricted gram-positive pathogen, responsible for various clinical presentations from mild epidermis infections to life threatened invasive diseases. Under COVID-19 pandemic,. the characteristics of the epidemic strains of GAS could be different. PURPOSE: To investigate epidemiological and molecular features of isolates from GAS infections among children in Beijing, China between January 2020 and December 2021. Antimicrobial susceptibility profiling was performed based on Cinical Laboratory Sandards Institute. Distribution of macrolide-resistance genes, emm types, and superantigens was examined by polymerase chain reaction. RESULTS: 114 GAS isolates were collected which were frequent resistance against erythromycin (94.74%), followed by clindamycin (92.98%), tetracycline (87.72%). Emm12 (46.49%), emm1 (25.44%) were dominant emm types. Distribution of ermB, ermA, and mefA gene was 93.85%, 2.63%, and 14.04%, respectively. Frequent superantigenes identified were smeZ (97.39%), speG (95.65%), and speC (92.17%). Emm1 strains possessed smeZ, ssa, and speC, while emm12 possessed smeZ, ssa, speG, and speC. Erythromycin resistance was predominantly mediated by ermB. Scarlet fever strains harbored smeZ (98.81%), speC (94.05%). Impetigo strains harbored smeZ (88.98%), ssa (88.89%), and speC (88.89%). Psoriasis strains harbored smeZ (100%). CONCLUSIONS: Under COVID-19 pandemic, our collections of GAS infection cutaneous diseases decreased dramatically. Epidemiological analysis of GAS infections among children during COVID-19 pandemic was not significantly different from our previous study. There was a correlation among emm, superantigen gene and disease manifestations. Long-term surveillance and investigation of emm types and superantigens of GAS prevalence are imperative.

Association between emphysema and other pulmonary computed tomography patterns in COVID-19 pneumonia.

To evaluate the chest computed tomography (CT) findings of patients with Corona Virus Disease 2019 (COVID-19) on admission to hospital. And then correlate CT pulmonary infiltrates involvement with the findings of emphysema. We analyzed the different infiltrates of COVID-19 pneumonia using emphysema as the grade of pneumonia. We applied open-source assisted software (3D Slicer) to model the lungs and lesions of 66 patients with COVID-19, which were retrospectively included. we divided the 66 COVID-19 patients into the following two groups: (A) 12 patients with less than 10% emphysema in the low-attenuation area less than -950 Hounsfield units (%LAA-950), (B) 54 patients with greater than or equal to 10% emphysema in %LAA-950. Imaging findings were assessed retrospectively by two authors and then pulmonary infiltrates and emphysema volumes were measured on CT using 3D Slicer software. Differences between pulmonary infiltrates, emphysema, Collapsed, affected of patients with CT findings were assessed by Kruskal-Wallis and Wilcoxon test, respectively. Statistical significance was set at p < 0.05. The left lung (A) affected left lung 20.00/affected right lung 18.50, (B) affected left lung 13.00/affected right lung 11.50 was most frequently involved region in COVID-19. In addition, collapsed left lung, (A) collapsed left lung 4.95/collapsed right lung 4.65, (B) collapsed left lung 3.65/collapsed right lung 3.15 was also more severe than the right one. There were significant differences between the Group A and Group B in terms of the percentage of CT involvement in each lung region (p < 0.05), except for the inflated affected total lung (p = 0.152). The median percentage of collapsed left lung in the Group A was 20.00 (14.00-30.00), right lung was 18.50 (13.00-30.25) and the total was 19.00 (13.00-30.00), while the median percentage of collapsed left lung in the Group B was 13.00 (10.00-14.75), right lung was 11.50 (10.00-15.00) and the total was 12.50 (10.00-15.00). The percentage of affected left lung is an independent predictor of emphysema in COVID-19 patients. We need to focus on the left lung of the patient as it is more affected. The people with lower levels of emphysema may have more collapsed segments. The more collapsed segments may lead to more serious clinical feature.

Multi-ligand molecular docking, simulation, free energy calculations and wavelet analysis of the synergistic effects between natural compounds baicalein and cubebin for the inhibition of the main protease of SARS-CoV-2.

Combination drugs have been used for several diseases for many years since they produce better therapeutic effects. However, it is still a challenge to discover candidates to form a combination drug. This study aimed to investigate whether using a comprehensive in silico approach to identify novel combination drugs from a Chinese herbal formula is an appropriate and creative strategy. We, therefore, used Toujie Quwen Granules for the main protease (Mpro) of SARS-CoV-2 as an example. We first used molecular docking to identify molecular components of the formula which may inhibit Mpro. Baicalein (HQA004) is the most favorable inhibitory ligand. We also identified a ligand from the other component, cubebin (CHA008), which may act to support the proposed HQA004 inhibitor. Molecular dynamics simulations were then performed to further elucidate the possible mechanism of inhibition by HQA004 and synergistic bioactivity conferred by CHA008. HQA004 bound strongly at the active site and that CHA008 enhanced the contacts between HQA004 and Mpro. However, CHA008 also dynamically interacted at multiple sites, and continued to enhance the stability of HQA004 despite diffusion to a distant site. We proposed that HQA004 acted as a possible inhibitor, and CHA008 served to enhance its effects via allosteric effects at two sites. Additionally, our novel wavelet analysis showed that as a result of CHA008 binding, the dynamics and structure of Mpro were observed to have more subtle changes, demonstrating that the inter-residue contacts within Mpro were disrupted by the synergistic ligand. This work highlighted the molecular mechanism of synergistic effects between different herbs as a result of allosteric crosstalk between two ligands at a protein target, as well as revealed that using the multi-ligand molecular docking, simulation, free energy calculations and wavelet analysis to discover novel combination drugs from a Chinese herbal remedy is an innovative pathway.

Risk Factors for Radiological Progression Within Admissive One Week in the Hospitalized COVID-19 Omicron Variant-Infected Patients.

Purpose: Recently, the SARS-CoV-2 Omicron variant was identified as responsible for a novel wave of COVID-19 worldwide. We perform a retrospective study to identify potential risk factors contributing to radiological progression in the COVID-19 patients due to the Omicron variant infection. These findings would provide guiding information for making clinical decisions that could improve the Omicron infection prognosis and reduce disease-related death. Methods: This is a retrospective cohort study from a single center in China. According to the radiological change within admissive one week, enrolled cases were divided into two groups: the progressive (1w-PD) and the stable or improved disease (1w-non-PD). Separate analyses were performed on patients stratified into subgroups using the Mann-Whitney U-test, the Fisher exact test, or the Chi-squared test and a multivariable logistic regression analysis. Results: Both the 1w-non-PD and 1w-PD cohorts displayed comparable asymptomatic infection, have similar underlying disease, impairment in respiratory function, coagulation dysfunction, tissue injury, SARS-CoV-2 viral load, and disease severity. However, the 1w-PD cohort was more inclined to cluster in populations presented with age between 41 and 65, higher CURB-65 scores, undetectable SARS-CoV-2 IgG, and lung affection. Based on the multiple logistic regression analysis, complicated bilateral and ground-glass opacities (GGOs) like pneumonia at admission were independent risk factors to radiological progression within admissive one week. Conclusion: This study provided preliminary data regarding disease progression in Omicron-infected patients that indicated the development of pneumonia in the context of Omicron infection was worthy of potential risk factors.

Warfarin anticoagulation management during the COVID-19 pandemic: The role of internet clinic and machine learning

Background: Patients who received warfarin require constant monitoring by hospital staff. However, social distancing and stay-at-home orders, which were universally adopted strategies to avoid the spread of COVID-19, led to unprecedented challenges. This study aimed to optimize warfarin treatment during the COVID-19 pandemic by determining the role of the Internet clinic and developing a machine learning (ML) model to predict anticoagulation quality. Methods: This retrospective study enrolled patients who received warfarin treatment in the hospital anticoagulation clinic (HAC) and “Internet + Anticoagulation clinic” (IAC) of the Nanjing Drum Tower Hospital between January 2020 and September 2021. The primary outcome was the anticoagulation quality of patients, which was evaluated by both the time in therapeutic range (TTR) and international normalized ratio (INR) variability. Anticoagulation quality and incidence of adverse events were compared between HAC and IAC. Furthermore, five ML algorithms were used to develop the anticoagulation quality prediction model, and the SHAP method was introduced to rank the feature importance. Results: Totally, 241 patients were included, comprising 145 patients in the HAC group and 96 patients in the IAC group. In the HAC group and IAC group, 73.1 and 69.8% (p = 0.576) of patients achieved good anticoagulation quality, with the average TTR being 79.9 ± 20.0% and 80.6 ± 21.1%, respectively. There was no significant difference in the incidence of adverse events between the two groups. Evaluating the five ML models using the test set, the accuracy of the XGBoost model was 0.767, and the area under the receiver operating characteristic curve was 0.808, which showed the best performance. The results of the SHAP method revealed that age, education, hypertension, aspirin, and amiodarone were the top five important features associated with poor anticoagulation quality. Conclusion: The IAC contributed to a novel management method for patients who received warfarin during the COVID-19 pandemic, as effective as HAC and with a low risk of virus transmission. The XGBoost model could accurately select patients at a high risk of poor anticoagulation quality, who could benefit from active intervention.

Psychosocial Determinants of Hand Hygiene, Facemask Wearing, and Physical Distancing During the COVID-19 Pandemic: A Systematic Review and Meta-analysis.

BACKGROUND: Hand hygiene, facemask wearing, and physical distancing play a crucial role in the prevention of the COVID-19 pandemic. Identifying the key psychosocial determinants of these precautionary behaviors contributes to effective intervention and policymaking for COVID-19 and future pandemics. PURPOSE: This study aimed to systematically review and meta-analyze available evidence on psychosocial determinants of the general population's practice of three precautionary behaviors, based on the Risk, Attitudes, Norms, Abilities, and Self-regulation (RANAS) framework. METHODS: Literature was identified by searching seven databases and relevant review papers. Observational and experimental studies targeting the general population (≥18 years) published between January 2020 to September 2021 were included. Pooled effect sizes were calculated with the inverse-variance method using random-effects models. RESULTS: A total of 51 studies (64 samples) were included in the qualitative synthesis, of which 30 studies (42 samples) were included in the meta-analysis. RANAS-based constructs including knowledge, pros attitudes, and perceived norms were identified as significant determinants of all three behaviors in the meta-analysis. Perceived susceptibility and cons attitudes showed no significant associations with any behaviors. Perceived severity, perceived control, self-efficacy, and behavioral intention were significantly associated with one or two behaviors. Country (western vs. eastern hemispheres) significantly moderated the effects of certain risk and ability factors. CONCLUSIONS: More research is needed with respect to the intention-behavior relationship, self-regulatory and reflexive factors of precautionary behaviors, as well as the exploration of the potential moderating effect of sociodemographic factors.

Identifying the psychosocial factors affecting the practice of three precautionary behaviors (hand hygiene, facemask wearing, and physical distancing) contributes to effective intervention and policymaking for the COVID-19 and future pandemics. Given the lack of summarized evidence, we conducted a systematic review and meta-analysis. Through seven databases and relevant review papers, we summarized the research findings of 51 observational studies that targeted the general population (≥18 years) and were published between January 2020 and September 2021. We found that (a) more knowledge, positive behavioral attitudes, and better compliance with the norms were associated with better practices of all three precautionary behaviors; (b) perceived susceptibility to the disease and negative behavioral attitudes were not associated with any precautionary behaviors; (c) higher levels of perceived disease severity, perceived behavioral control, self-efficacy, and behavioral intention were associated with better practices of one or two behaviors. In addition, we found that country (western vs. eastern hemispheres) differed in the relationship between psychosocial factors and behavioral practices. Specifically, both the association of perceived susceptibility with hand hygiene and the association of perceived severity with physical distancing were stronger among western populations. In contrast, the contribution of self-efficacy on the practice of physical distancing was stronger among eastern populations.

Association between intimate partner violence and prenatal anxiety and depression in pregnant women: a cross-sectional survey during the COVID-19 epidemic in Shenzhen, China.

OBJECTIVES: Intimate partner violence (IPV) against women remains a major global public health problem with harmful consequences for individuals and society. People's lifestyles have been greatly affected by the COVID-19 pandemic. This study investigated the prevalence of and relationship between IPV and anxiety and depression in pregnant Chinese women during the pandemic. DESIGN: Cross-sectional study. SETTING: This investigation was conducted in Shenzhen City, Guangdong Province, China from 15 September to 15 December 2020. PARTICIPANTS: A total of 3434 pregnant women were screened with the Abuse Assessment Screen Questionnaire to evaluate IPV and General Anxiety Disorder and Patient Health Questionnaire to evaluate symptoms of anxiety and depression, respectively. Pregnant women with perinatal health records at Shenzhen District Maternity and Child Healthcare Hospitals who consented to participate were enrolled. Women with psychotic disorders such as schizophrenia, mania or substance dependence and pregnant women who refused to participate were excluded. Data were analysed with the χ2 test and by logistic regression analysis. RESULTS: The prevalence of IPV among pregnant women was 2.2%. Mental violence was the most common type of violence (2.2%), followed by physical (0.6%) and sexual (0.7%) violence. The prevalence of anxiety and depression symptoms was 9.8% and 6.9%, respectively. After adjusting for covariates, there was a statistically significant association between IPV and prenatal anxiety (OR=4.207, 95% CI: 2.469 to 7.166) and depression (OR=3.864, 95% CI: 2.095 to 7.125). CONCLUSIONS: IPV increased the risk of prenatal anxiety and depression in pregnant women in China during the COVID-19 pandemic. Efforts should be made by the government and civil society to promote long-lasting antenatal interventions to ensure the safety and protect the mental health of pregnant women.

Study on Invulnerability of Material Emergency Transportation System Based on Three-Layer Interdependent Network

The material transportation capacity under emergency conditions is an important guarantee for the country to deal with war, epidemic outbreak, and other crisis situations. Under emergency conditions, some nodes of the material transportation system may fail to work normally, which may lead to the collapse of the whole system. Based on analyzing the characteristics of the material emergency transportation system, this article builds a three-layer interdependent network model and uses the improved M-L model to describe the failure propagation mechanism of node damage in the three-layer network. Then, the network model is attacked randomly, and the relationship between invulnerability of the three-layer network and the three main indexes of network flow, average degree, and probability of interdependence are studied. Afterwards, the propagation of cascading failure among three subnetworks in the interdependent network is analyzed and compared. This article provides a theoretical basis for building an efficient and robust material emergency transportation system.

Incidence analysis of 1 403 close contacts of corona virus disease 2019 patients in different contact modes

Objective: To study the exposure and incidence of close contacts of corona virus disease 2019 (COVID-19)cases. Methods The retrospective epidemiological method was used to describe and analyze the contact and incidence of 1 403 close contacts from January 23 to February 29, 2020, and the comparative analysis was made using X2 test. Results The frequency of close contacts was mainly occasional(78.62%). There was a difference in the composition of locations and ways of contact between contacts of local and nonlocal cases. The attack rate of close contacts of local cases w as 2.37%, and that of nonlocal cases was 0. The mean attack rate of all close contacts was 1.78%. Conclusion The incidence of close contacts has a correlation with the frequency and degree of contact. Living together results in the frequent contact, which further leads to multiple clusters in families. The attack rate of family cluster is significantly higher than that of other contacts. Implementing family prevention and control measures will help reduce the attack rate of family cluster.

Analysis and evaluation of the isolation medicine observation for close contacts of coronavirus disease 2019 in Jinan city

Objective: To analyze the isolation medicine observation for close contacts of Coronavirus disease 2019 (COVID-19) in Jinan City.

Successful combinatorial therapy of sirolimus and neuraminidase inhibitors in a patient with highly pathogenic avian influenza A (H5N6) virus: a case report

Background Highly pathogenic avian influenza A (H5N6) virus poses a continuous threat to human health since 2014. Although neuraminidase inhibitors (NAIs) are prescribed in most patients infected with the H5N6 virus, the fatality remains high, indicating the need for an improved treatment regimen. Sirolimus, an inhibitor of the mammalian target of rapamycin (mTOR), has been reported to reduce viral replication and improve clinical outcomes in severe H1N1 infections when combined with oseltamivir. Here, we report the first case of severe H5N6 pneumonia successfully treated by sirolimus and NAIs. Case Description A 22-year-old man developed high fever and chills on September 24, 2018 (Day-0) and was hospitalized on Day-3. Influenza A (H5N6) was identified on Day-6 from a throat swab specimen. Despite the administration of NAIs and other supportive measures, the patient’s clinical conditions and lung images showed continued deterioration, accompanied by persistently high viral titers. Consequently, sirolimus administration (rapamycin;2 mg per day for 14 days) was started on Day-12. His PaO2/FiO2 values and Sequential Organ Failure Assessment (SOFA) score gradually improved, and imaging outcomes revealed the resolution of bilateral lung infiltrations. The viral titer gradually decreased and turned negative on Day-25. Sirolimus and NAIs were stopped on the same day. The patient was discharged on Day-65. Based on observations from a 2-year follow-up, the patient was found to be in a good condition without complications. Conclusions In conclusion, sirolimus might be a novel and practical therapeutic approach to severe H5N6-associated pneumonia in humans.

Sprayable copper and copper–zinc nanowires inks for antiviral surface coating

Copper alloys are known for their high antimicrobial efficacy. Retrofitting high-touch surfaces in public space with solid copper components is expensive and often impractical. Directly coating copper onto these high-touch surfaces can be achieved with hot or cold spray, but the procedure is complicated and requires special equipment. This article reports on the development of sprayable copper and copper–zinc nanowire inks for antiviral surface coating applications. Our results show that copper nanowires inactivate the SARS-CoV-2 virus faster than bulk copper. And a trace amount of zinc addition has a significant effect in enhancing the virucidal effect. More importantly, these nanowire inks are sprayable. They can be easily applied on high-touch surfaces with a spray can. When combined with common chemical disinfectants, the copper-based nanowire ink spray may prolong the disinfecting effect well after application. SEM and TEM images of copper and copper–zinc nanowires that are sprayable for antiviral surface coating.

The Effect of Indoor Daylight Levels on Hospital Costs and Length of Stay of Patients Admitted to General Surgery.

BACKGROUND: Indoor daylight levels can directly affect the physical and psychological state of people. However, the effect of indoor daylight levels on the clinical recovery process of the patient remains controversial. This study was to evaluate the effect of indoor daylight levels on hospital costs and the average length of stay (LOS) of a large patient population in general surgery wards. METHODS: Data were collected retrospectively and analyzed of patients in the Second Affiliated Hospital of Zhejiang University, School of Medicine between January 2015 and August 2020. We measured daylight levels in the patient rooms of general surgery and assessed their association with the total hospital costs and LOS of the patients. RESULTS: A total of 2,998 patients were included in this study with 1,478 each assigned to two daylight level groups after matching. Overall comparison of hospital total costs and LOS among patients according to daylight levels did not show a significant difference. Subgroup analysis showed when exposed to higher intensity of indoor daylight, illiterate patients had lower total hospital costs (CNY ¥13070.0 vs. ¥15210.3, p = 0.018) and shorter LOS (7 vs. 10 days, p = 0.011) as compared to those exposed to a lower intensity. CONCLUSIONS: Indoor daylight levels were not associated with the hospital costs and LOS of patients in the wards of general surgery, except for those who were illiterate. It might be essential to design guidelines for medical staff and healthcare facilities to enhance the indoor environmental benefits of daylight for some specific populations.

Study on the Light Field Regulation of UVC-LED Disinfection for Cold Chain Transportation

In this paper, the pain point that cold chain transportation urgently needs for an efficient disinfection method is pointed out. Thus, this work aims at solving the problems and improving the disinfection efficiency in cold chain transportation. While Ultraviolet-C (UVC) irradiation is an effective method by which to kill viruses, it is difficult to apply the commonly used UVC-LED disinfection light source to ice-covered cold chain transportation due to its uneven light field distribution. Thus, the light field regulation of UVC-LED disinfection for cold chain transportation is studied. A UVC-LED chip with a wavelength of 275 nm was used as a light source, and parallel light was obtained by collimating lenses. Then, microlens array homogenization technology was used to shape the UVC light into a uniform light spot, with an energy space uniformity rate of 96.4%. Moreover, a simulation was conducted to compare the effects of the ice layer on the absorption of UVC light. Finally, an experiment was carried out to verify that the disinfection efficiency can be increased nearly by 30% with the proposed system by disinfecting E. coli (Escherichia coli), and the results indicate that the proposed system is an effective disinfection solution during cold chain transportation.

Wearing time and respiratory volume affect the filtration efficiency of masks against aerosols at different sizes.

Face masks are critical in preventing the spread of respiratory infections including coronavirus disease 2019 (COVID-19). Different types of masks have distinct filtration efficiencies (FEs) with differential costs and supplies. Here we reported the impact of breathing volume and wearing time on the inward and outward FEs of four different mask types (N95, surgical, single-use, and cloth masks) against various sizes of aerosols. Specifically, 1) Mask type was an important factor affecting the FEs. The FEs of N95 and surgical mask were better than those of single-use mask and cloth mask; 2) As particle size decreased, the FEs tended to reduce. The trend was significantly observed in FEs of aerosols with particle size < 1 µ m ; 3) After wearing N95 and surgical masks for 0, 2, 4, and 8 h, their FEs (%) maintained from 95.75 ± 0.09 to 100 ± 0 range. While a significant decrease in FEs were noticed for single-use masks worn for 8 h and cloth masks worn >2 h under deep breathing (30 L/min); 4) Both inward and outward FEs of N95 and surgical masks were similar, while the outward FEs of single-use and cloth masks were higher than their inward FEs; 5) The FEs under deep breathing was significantly lower than normal breathing with aerosol particle size <1 µ m. In conclusion, our results revealed that masks have a critical role in preventing the spread of aerosol particles by filtering inhalation, and FEs significantly decreased with the increasing of respiratory volume and wearing time. Deep breathing may cause increasing humidity and hence decrease FEs by increasing the airflow pressure. With the increase of wearing time, the adsorption capacity of the filter material tends to be saturated, which may reduce FEs. Findings may be used to provide information for policies regarding the proper use of masks for general public in current and future pandemics.

Quality Management for Point-Of-Care Testing of Pathogen Nucleic Acids: Chinese Expert Consensus.

COVID-19 continues to circulate globally in 2021, while under the precise policy implementation of China's public health system, the epidemic was quickly controlled, and society and the economy have recovered. During the pandemic response, nucleic acid detection of SARS-CoV-2 has played an indispensable role in the first line of defence. In the cases of emergency operations or patients presenting at fever clinics, nucleic acid detection is required to be performed and reported quickly. Therefore, nucleic acid point-of-care testing (POCT) technology for SARS-CoV-2 identification has emerged, and has been widely carried out at all levels of medical institutions. SARS-CoV-2 POCT has served as a complementary test to conventional polymerase chain reaction (PCR) batch tests, thus forming an experimental diagnosis platform that not only guarantees medical safety but also improves quality services. However, in view of the complexity of molecular diagnosis and the biosafety requirements involved, pathogen nucleic acid POCT is different from traditional blood-based physical and chemical index detection. No guidelines currently exist for POCT quality management, and there have been inconsistencies documented in practical operation. Therefore, Shanghai Society of Molecular Diagnostics, Shanghai Society of Laboratory Medicine, Clinical Microbiology Division of Shanghai Society of Microbiology and Shanghai Center for Clinical Laboratory have cooperated with experts in laboratory medicine to generate the present expert consensus. Based on the current spectrum of major infectious diseases in China, the whole-process operation management of pathogen POCT, including its application scenarios, biosafety management, personnel qualification, performance verification, quality control, and result reporting, are described here. This expert consensus will aid in promoting the rational application and robust development of this technology in public health defence and hospital infection management.