Design and Coverage Path Planning of a Disinfection Robot

Eliminating pathogen exposure is an important approach to control outbreaks of epidemics such as COVID-19 (coronavirus disease 2019). To deal with pathogenic environments, using disinfection robots is a practicable choice. This research formulates a 3D (three-dimensional) spatial disinfection strategy for a disinfection robot. First, a disinfection robot is designed with an extensible control framework for the integration of additional functions. The robot has eight degrees of freedom that can handle disinfection tasks in complex 3D environments where normal disinfection robots lack the capability to ensure complete disinfection. An ingenious clamping mechanism is designed to increase flexibility and adaptability. Secondly, a new coverage path planning algorithm targeted at the spraying area is used. This algorithm aims to achieve an optimal path via the rotating calipers algorithm after transformation between a 2D (two-dimensional) array and 3D space. Finally, the performance of the designed robot is tested through a series of simulations and experiments in various spaces that humans usually live in. The results demonstrate that the robot can effectively perform disinfection tasks both in computer simulation and in reality.

Emergency surgical strategies for patients with acute abdomen during the COVID-19 outbreak.

Objective: To investigate the emergency surgical strategies for patients with acute abdomen during the Corona Virus Disease 2019 (COVID-19) outbreak. Method(s): The retrospective and descriptive study was conducted. The clinical data of 20 patients with acute abdomen who were admitted to the Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology between January 18, 2020 and February 10, 2020 were collected. There were 13 males and 7 females, aged from 25 to 82 years, with an average age of 57 years. All the patients with emergency surgeries received pulmonary computed tomography (CT) examination before surgery, and completed nucleic acid detection in throat swab if necessary. Patients excluded from COVID-19 underwent regular anesthesia, suspected and confirmed cases were selected a proper anesthesia based on their medical condition and surgical procedure. Patients excluded from COVID-19 underwent emergency surgeries following the regular procedure, suspected and confirmed cases underwent emergency surgeries following the three-grade protection. Observation indicators: (1) surgical situations;(2) postoperative situations. Measurement data with normal distribution were represented as average (range). Count data were described as absolute numbers. Result(s): (1) Surgical situations: of the 20 patients with acute abdomen, 16 patients were excluded from COVID-19, and 4 were not excluded. All the 20 patients underwent emergency abdominal surgeries successfully, of whom 2 received surgeries under epidural anesthesia (including 1 with open appendectomy, 1 with open repair of duodenal bulbar perforation), 18 received surgeries under general anesthesia (including 9 with laparoscopic repair of duodenal bulbar perforation, 3 with open partial enterectomy, 3 with laparoscopic appendectomy, 1 with laparoscopic left hemicolectomy, 1 with laparoscopic right hemicolectomy, 1 with cholecystostomy). The operation time of patients was 32-194 minutes, with an average time of 85 minutes. The volume of intraoperative blood loss was 50-400 mL, with an average volume of 68 mL. (2) Postoperative situations: 16 patients excluded from COVID-19 preopratively were treated in the private general ward postoperatively. One of the 16 patients had fever at the postoperative 5th day and was highly suspected of COVID-19 after an emergency follow-up of pulmonary CT showing multiple ground-glass changes in the lungs. The patient was promptly transferred to the isolation ward for treatment, and results of nucleic acid detection in throat swab showed double positive. Medical history described by the patient showed that the patient and family members were residents of Wuhan who were not isolated at home during the epidemic. There was no way to confirm whether they had a history of exposure to patients with COVID-19. Medical staffs involved in this case did not show COVID-19 related symptoms during 14 days of medical observation. The other 15 patients recovered well postoperatively. The 4 patients who were not excluded from COVID-19 preoperatively based on medical history and results of pulmonary CT examination were directly transferred to the isolation ward for treatment postoperatively. They were excluded from COVID-19 for two consecutive negative results of nucleic acid detection in the throat swab and recovered well. Two of the 20 patients with acute abdomen had postoperative complications. One had surgical incision infection and recovered after secondary closure following opening incision, sterilizing and dressing, the other one had intestinal leakage and was improved after conservative treatment by abdominal drainage. There was no death in the 20 patients with acute abdomen. Conclusion(s): Patients with acute abdomen need to be screened through emergency forward. Patients excluded from COVID-19 undergo emergency surgeries following the regular procedure, and patients not excluded from COVID-19 undergo emergency surgeries following the three-grade protection. The temperature, blood routine test and other l boratory examinations are performed to monitor patients after operation, and the pulmonary CT and throat nucleic acid tests should be conducted if necessary. Patients excluded from COVID-19 preopratively are treated in the private general ward postoperatively, and they should be promptly transferred to the isolation ward for treatment after being confirmed. Patients who are not excluded from COVID-19 preoperatively based on medical history should be directly transferred to the isolation ward for treatment postoperatively.Copyright © 2020 by the Chinese Medical Association.

Emergency surgical strategies for patients with acute abdomen during the COVID-19 outbreak.

Objective: To investigate the emergency surgical strategies for patients with acute abdomen during the Corona Virus Disease 2019 (COVID-19) outbreak. Method(s): The retrospective and descriptive study was conducted. The clinical data of 20 patients with acute abdomen who were admitted to the Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology between January 18, 2020 and February 10, 2020 were collected. There were 13 males and 7 females, aged from 25 to 82 years, with an average age of 57 years. All the patients with emergency surgeries received pulmonary computed tomography (CT) examination before surgery, and completed nucleic acid detection in throat swab if necessary. Patients excluded from COVID-19 underwent regular anesthesia, suspected and confirmed cases were selected a proper anesthesia based on their medical condition and surgical procedure. Patients excluded from COVID-19 underwent emergency surgeries following the regular procedure, suspected and confirmed cases underwent emergency surgeries following the three-grade protection. Observation indicators: (1) surgical situations;(2) postoperative situations. Measurement data with normal distribution were represented as average (range). Count data were described as absolute numbers. Result(s): (1) Surgical situations: of the 20 patients with acute abdomen, 16 patients were excluded from COVID-19, and 4 were not excluded. All the 20 patients underwent emergency abdominal surgeries successfully, of whom 2 received surgeries under epidural anesthesia (including 1 with open appendectomy, 1 with open repair of duodenal bulbar perforation), 18 received surgeries under general anesthesia (including 9 with laparoscopic repair of duodenal bulbar perforation, 3 with open partial enterectomy, 3 with laparoscopic appendectomy, 1 with laparoscopic left hemicolectomy, 1 with laparoscopic right hemicolectomy, 1 with cholecystostomy). The operation time of patients was 32-194 minutes, with an average time of 85 minutes. The volume of intraoperative blood loss was 50-400 mL, with an average volume of 68 mL. (2) Postoperative situations: 16 patients excluded from COVID-19 preopratively were treated in the private general ward postoperatively. One of the 16 patients had fever at the postoperative 5th day and was highly suspected of COVID-19 after an emergency follow-up of pulmonary CT showing multiple ground-glass changes in the lungs. The patient was promptly transferred to the isolation ward for treatment, and results of nucleic acid detection in throat swab showed double positive. Medical history described by the patient showed that the patient and family members were residents of Wuhan who were not isolated at home during the epidemic. There was no way to confirm whether they had a history of exposure to patients with COVID-19. Medical staffs involved in this case did not show COVID-19 related symptoms during 14 days of medical observation. The other 15 patients recovered well postoperatively. The 4 patients who were not excluded from COVID-19 preoperatively based on medical history and results of pulmonary CT examination were directly transferred to the isolation ward for treatment postoperatively. They were excluded from COVID-19 for two consecutive negative results of nucleic acid detection in the throat swab and recovered well. Two of the 20 patients with acute abdomen had postoperative complications. One had surgical incision infection and recovered after secondary closure following opening incision, sterilizing and dressing, the other one had intestinal leakage and was improved after conservative treatment by abdominal drainage. There was no death in the 20 patients with acute abdomen. Conclusion(s): Patients with acute abdomen need to be screened through emergency forward. Patients excluded from COVID-19 undergo emergency surgeries following the regular procedure, and patients not excluded from COVID-19 undergo emergency surgeries following the three-grade protection. The temperature, blood routine test and other l boratory examinations are performed to monitor patients after operation, and the pulmonary CT and throat nucleic acid tests should be conducted if necessary. Patients excluded from COVID-19 preopratively are treated in the private general ward postoperatively, and they should be promptly transferred to the isolation ward for treatment after being confirmed. Patients who are not excluded from COVID-19 preoperatively based on medical history should be directly transferred to the isolation ward for treatment postoperatively.Copyright © 2020 by the Chinese Medical Association.

Macrophage membrane-biomimetic adhesive polycaprolactone nanocamptothecin for improving cancer-targeting efficiency and impairing metastasis

The recent remarkable success and safety of mRNA lipid nanoparticle technology for producing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines has stimulated intensive efforts to expand nanoparticle strategies to treat various diseases. Numerous synthetic nanoparticles have been developed for pharmaceutical delivery and cancer treatment. However, only a limited number of nanotherapies have enter clinical trials or are clinically approved. Systemically administered nanotherapies are likely to be sequestered by host mononuclear phagocyte system (MPS), resulting in suboptimal pharmacokinetics and insufficient drug concentrations in tumors. Bioinspired drug-delivery formulations have emerged as an alternative approach to evade the MPS and show potential to improve drug therapeutic efficacy. Here we developed a biodegradable polymer-conjugated camptothecin prodrug encapsulated in the plasma membrane of lipopolysaccharide-stimulated macrophages. Polymer conjugation revived the parent camptothecin agent (e.g., 7-ethyl-10-hydroxy-camptothecin), enabling lipid nanoparticle encapsulation. Furthermore, macrophage membrane cloaking transformed the nonadhesive lipid nanoparticles into bioadhesive nanocamptothecin, increasing the cellular uptake and tumor-tropic effects of this biomimetic therapy. When tested in a preclinical murine model of breast cancer, macrophage-camouflaged nanocamptothecin exhibited a higher level of tumor accumulation than uncoated nanoparticles. Furthermore, intravenous administration of the therapy effectively suppressed tumor growth and the metastatic burden without causing systematic toxicity. Our study describes a combinatorial strategy that uses polymeric prodrug design and cell membrane cloaking to achieve therapeutics with high efficacy and low toxicity. This approach might also be generally applicable to formulate other therapeutic candidates that are not compatible or miscible with biomimetic delivery carriers. © 2022 The Authors

Equity Promotion in Online Resource Allocation

We consider online resource allocation under a typical nonprofit setting, where limited or even scarce resources are administered by a not-for-profit organization like a government. We focus on the internal-equity by assuming that arriving requesters are homogeneous in terms of their external factors like demands but heterogeneous for their internal attributes like demographics. Specifically, we associate each arriving requester with one or several groups based on their demographics (i.e., race, gender, and age), and we aim to design an equitable distributing strategy such that every group of requesters can receive a fair share of resources proportional to a preset target ratio. We present two LP-based sampling algorithms and investigate them both theoretically (in terms of competitive-ratio analysis) and experimentally based on real COVID-19 vaccination data maintained by the Minnesota Department of Health. Both theoretical and numerical results show that our LP-based sampling strategies can effectively promote equity, especially when the arrival population is disproportionately represented, as observed in the early stage of the COVID-19 vaccine rollout.

Research on International Benchmarking of Building China's Transport Power

In order to objectively evaluate the international status and level of China's transport development under the background of building a transport power, this paper selects major countries in the world to carry out international benchmarking analysis from the perspective of international comparison. Firstly, the evaluation index system of transport power construction suitable for international comparison is proposed by focusing on the positioning of indicators and construction principles, and the definition, statistical caliber, calculation formula, data source and other basic elements of indicators are further clarified. Secondly, by determining the evaluation scope, standardizing treatment, and setting weights, the two methods of cluster analysis and index weighting are used for calculation and analysis and mutual comparison. Finally, the results of the two methods show that: China's transport development level is generally in the third echelon, higher than the main BRICS countries, but there is still a significant gap compared with the United States, Japan, Germany, Britain, France, and other countries. China is speeding up its efforts to build into a transport power. In recent years, China's transport development has been at the forefront and at a high speed, with a good momentum of development. During the COVID-19 pandemic, the transport growth rate in China was significantly faster than that of other countries, and the gap between China and the world's transport power is narrowing at a faster pace. © 2022 IEEE.

The Sickest COVID-19 Patients During the First Wave of the Epidemic: Strong Clinical Evidence for Acute Tubular Injury

Background: From March through June 2020, SARS-CoV-2 virus surged through the New York Metropolitan area, killing 43,000 in NY and NJ. The sickest patients had both respiratory failure and severe acute kidney injury (AKI), were intubated and on dialysis. Method(s): Seventy intubated patients with severe covid and severe AKI requiring dialysis were treated in 2 north Jersey hospital ICU during this period. Their records were reviewed, focusing particularly during the period of AKI onset to identify potential renal insults - hypotension and shock, secondary infections, and inflammation markers. Result(s): Following admission, respiratory failure quickly progressed, and intubation occurred 3.3 +/- 3.7 days after admission. AKI became evident 1.5 days later (4.7 +/- 4.8 days after admission), and dialysis was initiated 5.4 +/- 6.6 days after AKI onset. Serum creatinine at the start of dialysis was 6.44 +/- 3.40 mg/dl. Around the onset of AKI (start of dialysis +/- 5 days), hemodynamic and clinical instability were rampant. Hypotension requiring vasopressors occurred in 83%;oliguria developed in 79% and worsened to anuria in 33%. Bacteremia and fungemia complicated this period in 28% and 10%. The inflammatory markers - CRP, d-dimer, ferritin, interleukin-6 and ESR, were extremely elevated. Fifty-two patients (74%) died during the hospitalization, 17.7 +/- 11.8 days from admission. Renal function improved in only 1 of these patients. Eighteen patients (26%) survived, and were discharged 63 +/- 15 days after admission. Fifteen (83%) of them regained renal function after requiring dialysis for 20 +/- 15 days. Their serum creatinine decreased to 1.15 +/- 0.63 mg/dl at discharge. Some went through a polyuric phase. Most of these survivors had severe medical problems. Over the next 3.5 months, 5 of them died. Conclusion(s): The following clinical aspects were highly suggestive of acute tubular injury: - onset of AKI during severe hemodynamic instability, intubation, pressor use, secondary infections and intense inflammation;- the rapid progression to uremia;- oliguria early in AKI;some with polyuric phase that preceded improvement of renal function;- short period of dialysis and marked improvement of renal function 8 weeks after onset in 83% of the survivors.

Risk Prediction for AKI in Patients Hospitalized With COVID-19: Withstanding Variants Over Time

Background: Acute kidney injury (AKI) is common in patients hospitalized with COVID-19, predictive models for AKI are lacking. We aimed to develop the best predictive model for AKI and assess performance over time. Method(s): Patients with positive SARS CoV-2 PCR hospitalized between 3/1/2020 to 1/14/2022 at 19 Texas hospitals were included. Those with AKI present on admission were excluded. Comorbidities, demographics, baseline laboratory data, and inflammatory biomarkers were obtained from the EHR and used to build nested models for AKI in an inception cohort. Models were validated in four out-of-time cohorts. Model discrimination and calibration measures were compared to assess performance. Result(s): Of 13,468 patients, 5,676 were in the Inception Cohort and 7,792 in subsequent validation cohorts grouped based on predominance of COVID variants, with cohorts 1 and 3 containing a mix of variants, cohort 2 corresponding to Delta predominance, and cohort 4 to Omicron. Prevalence of AKI was 13.7% in inception and 12.6%, 12.4%, 13.3%, and 14.4% in the validation cohorts. Proportion of AKI stages 2 or 3 vs. 1 was lower in the Omicron-dominant cohort 4 compared to the inception cohort (28/139 vs. 257/776, P=0.008), but was no different for cohorts 1-3. The final model containing demographics, comorbidities and baseline WBC, hemoglobin, hsCRP, ferritin, and D-dimer, had an AUC=0.781 (95% CI, 0.763, 0.799). Compared to the inception cohort, discrimination by AUC (validation 1: 0.785 [0.760, 0.810], P=0.14, validation 2: 0.754 [0.716, 0.795], P=0.14, validation 3: 0.778 [0.751, 0.806], P=0.14, and validation 4: 0.743 [0.695, 0.789], P=0.14) and calibration by ECI (validation 1: 0.116 [0.041, 0.281], P=1.0, validation 2: 0.081 [0.045, 0.295], P=0.64, validation 3: 0.055 [0.030, 0.162], P=1.0, and validation 4: 0.120 [0.043, 0.472], P=0.50) showed stable performance over time. Conclusion(s): Using demographics, comorbidities, admission laboratory values, and inflammatory biomarkers, we developed and externally validated a model to accurately predict AKI in hospitalized patients with COVID-19. A lower proportion of patients hospitalized during the Omicron-dominant period of the pandemic experienced severe AKI, but our predictive model withstood changes in practice patterns and virus variants.

PANGO: Prediction Model Based on Clustering of Time Series for Traffic Flow to Venues

With the increasing number of venues in the city, it provides better services for people. However, the ever-changing flow of people has also brought challenges to the management of venues, especially under the current regular prevention and control measures for COVID-19. Therefore, it is extremely necessary to propose a suitable prediction model for pedestrian volume to venues. The timing characteristics of venue's traffic flow determine that the accuracy of the prediction results by applying classical prediction models is unsatisfactory. In order to resolve the problem, in this paper, a Long Short Term Memory network (LSTM) combined with clustering of time series named PANGO is proposed. In PANGO, the temporal clustering is proposed to solve the short-term dependence of traffic flow data, while the long-term cycle prediction model is applied to obtain the longterm cycle characteristics, so as to improve the accuracy of prediction. Finally, the results of multi-dimensional experiments show that the prediction accuracy of PANGO model is improved by 11.8% compared with the traditional LSTM model. © 2022 IEEE.

COVID-19 AND KIDNEY TRANSPLANT RECIPIENTS: IMMUNOSUPPRESSION MANAGEMENT AND OUTCOMES

The COVID-19 pandemic raises important questions about immunosuppression management and outcomes in kidney transplant recipients. Kidney transplant recipients with positive SARS-CoV2 PCR seen in outpatient clinics or hospitalized at University and Parkland Hospitals from 3/1-10/1/20 were followed for 90 days. Univariate and multivariate backward selection logistic regression was used to identify risk factors for a composite event of AKI, ICU admission, or death. Non-parametric methods compared biomarkers based on changes in immunosuppressive drugs. Of 59 patients, mean age (SD) was 51 (14) years, 35 (59%) were male, 13 (22%) black and 36 (61%) Hispanic. 29 (50%) had a baseline eGFR <60 mL/min/1.73 m2, 52 (88%) had hypertension and 33 (56%) diabetes. 55 (93%) were on calcineurin inhibitors (CNI) and 49 (83%) on an antimetabolite at baseline. 6 (10%) were treated for acute rejection in the 12 months prior. Initial ferritin level was higher in those who had CNI dose decreased or discontinued vs. those with CNI unchanged, median (IQR) 1271 (839-1932) vs 283 (124-569) ng/mL, p=0.0002. Patients who stopped CNI showed significantly higher peak hsCRP values than those maintained on the same dose, median (IQR) 344 (145-374) vs 41 (22-116) vs mg/L, p=0.03. There were 31 composite events, 43 hospitalizations, 13 ICU admissions, and 12 deaths. Of 52 patients with creatinine values, 29 (56%) had AKI, of which 10 (35%) required RRT. 13 (46%) had recovery of AKI at 90 days, defined as serum creatinine within 10% of baseline. Factors associated with the composite are shown (table). eGFR< 60 and peak hsCRP remained in the multivariable model associated with the composite, with area under the curve =0.89. 1OR per 1 unit increase X 109/L1 Over half of kidney transplant patients with COVID-19 had AKI and 73% required hospitalization. Elevated markers of inflammation were associated with changes in CNI regimen. An eGFR<60 and higher peak hsCRP were associated with increased risk of death, ICU admission, or AKI.

In the Storm of COVID-19: College Students’ Perceived Challenges With Virtual Learning

Using open-ended questions, this study surveyed over 450 undergraduate students to gain insights into their perceptions of the virtual learning environment due to the COVID-19 pandemic. Results reveal the rapid transition of most courses to online teaching because of COVID-19 was very challenging for students. A conceptual model was developed on the challenges of virtual learning. The findings reveal three major challenges for virtual learning: learning environment, motivation, and learning effectiveness. Environment and personal characteristics contributed to the lack of motivation to learn. Furthermore, students’ learning behavior and professors’ unpreparedness, and subject matter caused decreased learning effectiveness. The findings of the study can help decision makers at colleges and universities make informed decisions when adopting and/or modifying different teaching/learning environments, as well as professors in developing effective teaching strategies and pedagogy. © 2022, North American Business Press. All rights reserved.

[Epidemiological characteristics of imported COVID-19 cases in Tianjin].

Objective: To understand the epidemiological characteristics of imported COVID-19 cases in Tianjin, and provide references for risk assessment and control of imported COVID-19 cases. Methods: The information of imported COVID-19 cases were obtained from National Notifiable Disease Report System of China CDC. The data of imported COVID-19 cases reported from Tianjin airport and epidemiological surveys by CDCs at all levels from March 15, 2020 to August 31, 2021 were collected and analyzed by using software Excel 2010, SPSS 25.0 and R. Results: From March 15, 2020 to August 31, 2021, a total of 606 imported cases of COVID-19 were reported in Tianjin, in which 552 cases were finally included in the analysis. The male to female ratio of the cases was 1.8∶1, the age of the cases ranged from 3 to 77 years, and the cases were mainly reported in age group 20-39 years (59.8%). The areas where the imported case sojourned within 14 days included Europe (242 cases, 43.8%), Africa (139 cases, 25.2%), Americas (85 cases, 15.4%) and Asia (86 cases, 15.6%). The proportion of confirmed cases in autumn and winter was relatively high. During the study period, the proportion of infected persons found in custom entry quarantine decreased, and the proportion of persons with personal health declaration and under medical isolation observation increased. The interval between entry and diagnosis of infected persons tended to increase. Conclusion: The proportion of imported COVID-19 cases detected on the first day of entry at Tianjin airport decreased, and the interval to detect the infected persons trended to increase, to which close attention must be paid.

AKI in inpatients with COVID-19: Risk factors and mortality

Background: AKI in hospitalized patients with COVID-19 is a common adverse complication. Our aim was to investigate risk factors associated with AKI and whether AKI in this setting is independently associated with in-hospital mortality at 30 days. Methods: All adult patients admitted with a positive SARS-CoV-2 PCR between 3 /2021 to 1/2021 to nineteen hospitals who had a COVID-associated billing diagnosis and no history of ESKD or kidney transplant were included. AKI was defined according to the Kidney Disease Improving Global Outcomes guidelines. Risk factors associated with AKI were evaluated with univariable and multivariable logistic regression, and mortality was evaluated using Kaplan-Meier and Cox Proportional Hazards models. Results: The study cohort included 9,681 patients, of which 3,666 (38%) met criteria for AKI. Compared with patients without AKI, patients with AKI were older [mean (SD) age 67 (16) vs. 60 (18) years], more likely to be male (58% vs. 47%), and more likely to be black (21% vs. 15%). Patients with AKI were also more likely to have diabetes mellitus (52% vs. 32%), hypertension (78% vs. 57%), CKD (55% vs. 17%), and coronary artery disease (20% vs. 11%). Patients with AKI were also more likely to be on ACEi/ ARB on admission (51% vs. 37%), require mechanical ventilation (21% vs. 3.2%) or have higher WBC, hs-CRP, ferritin, D-dimer, and cardiac troponin). P-values were <0.001 for all of the aforementioned comparisons. Risk factors significantly associated with AKI in the multivariable model included age, sex, race, hypertension, CKD, diabetes, ACEi or ARB on admission, mechanical ventilation, WBC on admission, hs-CRP, ferritin, d dimer and troponin. Death occurred more frequently in patients with AKI (22.1%;n=811) than in those without (3%;n=178). Patient with AKI had higher mortality risk as compared to those without AKI, hazard ratio (HR) 3.08 (95% CI 2.56-3.71), that remained significant even after controlling for all variables associated with AKI, such as age, sex, race, comorbidities, inflammatory biomarkers, elevated troponin, and COVID-related treatments, HR 1.64 (95% CI 1.34-2.01). Conclusions: Patients with COVID-19 who develop AKI have a higher mortality. We found risk factors associated with AKI in the setting of COVID, and that the increased mortality risk associated with AKI in COVID-19 is independent of these factors.

AKI prediction and recovery in hospitalized patients with COVID-19

Background: AKI is a complication in patients hospitalized with COVID-19 and is associated with poor outcomes. We aimed to develop predictive models for AKI development and recovery in patients hospitalized with COVID-19. Methods: Patients with a positive SARS-CoV2 PCR admitted to 19 Texas hospitals from 3/13/2020-1/1/2021 were included. AKI presence and stages were determined using KDIGO guidelines. Individuals with AKI present on admission (POA) were excluded for predictive models. Patients were followed for 90 days to evaluate for renal recovery (serum creatinine ≤1.1 times baseline). Nested models for AKI were built using logistic regression: Model 1 included age, sex, race, smoking status, presence of hypertension (HTN), diabetes (DM), chronic kidney disease (CKD), coronary artery disease (CAD), and chronic heart failure (CHF), and use of ACEI/ARB;Model 2, added admission WBC, hs-CRP, and hemoglobin;Model 3, added ferritin and D-Dimer to Model 2 to assess for accuracy improvements. 10-fold stratified cross validation was done to evaluate model performance. Results: Of 8392 patients, 2702 (32%) had AKI, of which 2281 (84%) recovered by 90 days: 92% of stage 1, 75% of stage 2, and 40% of stage 3 AKI, p for trend <0.001. After excluding AKI present on admission, 776 of 5671 developed AKI during the hospitalization. Percentages of AKI stages 1, 2 and 3 were 67%, 8%, and 25%. Overall, 152 (20%) of 776 required RRT. Patients with AKI were older, more likely to be male, black, and have hypertension, diabetes, coronary artery disease, congestive heart failure, and CKD. The interval improvement of each AKI predictive model was statistically significant, with last model AUC of 78.1 (95% CI 76.3%-79.9%) and all p<0.001. The final model had improvement in all metrics when compared to Models 1 and 2, with a sensitivity of 69%, specificity 76%, positive predictive value 32%, negative predictive value 94%, positive likelihood ratio 3.02, and negative likelihood ratio 0.40. Conclusions: AKI is common among patients hospitalized with COVID-19, but a large proportion recover renal function by 90 days. Recovery rate is lower based on stepwise higher stages of AKI. Addition of inflammatory biomarkers to demographics and medical comorbidities can improve prediction of AKI in this patient population.

Milvus: A Purpose-Built Vector Data Management System

Recently, there has been a pressing need to manage high-dimensional vector data in data science and AI applications. This trend is fueled by the proliferation of unstructured data and machine learning (ML), where ML models usually transform unstructured data into feature vectors for data analytics, e.g., product recommendation. Existing systems and algorithms for managing vector data have two limitations: (1) They incur serious performance issue when handling large-scale and dynamic vector data;and (2) They provide limited functionalities that cannot meet the requirements of versatile applications. This paper presents Milvus, a purpose-built data management system to efficiently manage large-scale vector data. Milvus supports easy-to-use application interfaces (including SDKs and RESTful APIs);optimizes for the heterogeneous computing platform with modern CPUs and GPUs;enables advanced query processing beyond simple vector similarity search;handles dynamic data for fast updates while ensuring efficient query processing;and distributes data across multiple nodes to achieve scalability and availability. We first describe the design and implementation of Milvus. Then we demonstrate the real-world use cases supported by Milvus. In particular, we build a series of 10 applications (e.g., image/video search, chemical structure analysis, COVID-19 dataset search, personalized recommendation, biological multi-factor authentication, intelligent question answering) on top of Milvus. Finally, we experimentally evaluate Milvus with a wide range of systems including two open source systems (Vearch and Microsoft SPTAG) and three commercial systems. Experiments show that Milvus is up to two orders of magnitude faster than the competitors while providing more functionalities. Now Milvus is deployed by hundreds of organizations worldwide and it is also recognized as an incubation-stage project of the LF AI & Data Foundation. Milvus is open-sourced at https://github.com/milvus-io/milvus. © 2021 Owner/Author.

Neuroleptic malignant syndrome in a COVID-19 patient. (Special Issue: Immunopsychiatry of COVID-19 pandemic.)

This paper reports the first two cases of Coronavirus Disease 2019 (COVID-19) who were receiving intensive care including favipiravir, and were clinically diagnosed with neuroleptic malignant syndrome (NMS) to focus attention on NMS in COVID-19 management. Case 1: A 46-year-old-man with acute respiratory distress syndrome (ARDS) caused by COVID-19 infection was being administered favipiravir. Fentanyl, propofol, and rocuronium were also given. On day 3, midazolam administration was initiated for deep sedation. On day 5, his high body temperature increased to 41.2 degrees C, creatine kinase level elevated, and he developed tachycardia, tachypnea, altered consciousness, and diaphoresis. NMS was suspected, and supportive therapy was initiated. High-grade fever persisted for 4 days and subsided on day 9. Case 2: A 44-year-old-man with ARDS caused by COVID-19 infection was being treated with favipiravir. On day 5, risperidone was started for delirium. On day 7, his body temperature suddenly increased to 40.8 degrees C, his CK level elevated, and he developed tachycardia, tachypnea, altered consciousness, and diaphoresis. NMS diagnosis was confirmed, and both, favipiravir and risperidone were discontinued on day 8. On the same day, his CK levels decreased, and his body temperature normalized on day 9. Patients with COVID-19 infection frequently require deep sedation and develop delirium;therefore, more attention should be paid to the development of NMS in patients who are being administered such causative agents. The mechanism underlying the occurrence of NMS in COVID-19 patients treated with favipiravir remains unknown. Therefore, careful consideration of NMS development is necessary in the management of COVID-19 patients.

Research on an evaluation method for home-based network teaching quality based on analytic hierarchy process

Students can't go to school during COVID-19 pandemic, so schools across China actively responded to the call of Ministry of Education to 'stop classes without stopping studying', that is, through the online platform, teachers can teach and students can study at home. Therefore, it is important to evaluate home-based teaching quality via Network. Based on the analytic hierarchy process, this paper selects five indicators, i.e. learning users, teaching content, teaching methods, teaching platform and teaching effect, to build an evaluation system of online teaching effect and evaluate online teaching quality. It is shown that the impact of the home environment under the student user criterion module, the perfect teaching platform function under the teaching platform criterion module, and the student learning requirements under the student user criterion module have the most significant impact on the effect of online teaching in the evaluation system, while the basic knowledge is less influential. The evaluation system provides technical support for the evaluation of online teaching effects. © 2020 IEEE.

Landscape of SARS-CoV-2 spike protein-interacting cells in human tissues

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic. However, the mechanism of tissue tropism of SARS-CoV-2 remains unclear. Here, recombinant receptor-binding subdomain 1 of spike protein of SARS-CoV-2 (RBD-SD1) was used as a probe to investigate the potential tropism of SARS-CoV-2 in thirty-three types of normal human tissues. RBD-SD1 probe was observed to interact with cells in reported SARS-CoV-2 infected organs. Interestingly, the RBD-SD1 probe strongly interacted with bone marrow cells in an angiotensin-converting enzyme 2 (ACE2)-independent manner. In addition, SARS-CoV-2 induced the ACE2 mRNA expression in human primary bone marrow cells, suggesting human bone marrow cells may be sensitive to SARS-CoV-2 infection. Therefore, human bone marrow cells could be strongly infected by SARS-CoV-2, which may play an important role in the pathogenesis of COVID-19. These findings provide a deeper understanding of SARS-CoV-2 infection routes, thus contributing to the treatment of COVID-19.

Investing a Better Future: Education for Sustainable Development as a Means to Strengthen the Environmental Education

Since the outbreak of the epidemic, the environment education and the education of sustainable development became the mainfocus once again. It is because some citizens lack consciousness of ecological civilization and sustainable development, caused environmental pollution, indiscriminate killing of wild animals, destruction of social public health, injury and sacrifice of people's physical and mental health, disturbance of urban and rural social life order, etc. The outbreak of the novel coronavirus pneumonia undoubtedly confirmed the urgency of strengthening the global citizens' education for sustainable development. This serious epidemic related to the sale and consumption of wild animals is a wake-up call again. It is necessary to reexamine the relationship between man and nature and the way of human behavior. Education is the key factor for the implementation of sustainable development. Good health and well-being, and quality education are the third and fourth goal for sustainable development proposed by the United Nations. Through content analysis and case analysis, this paper indicated that teachers' educational ability for sustainable development is a professional ability that higher education institutes should apply education for sustainable development as a means to strengthen the environmental education. Teachers identify with the concept of sustainable development education and are willing to practice the values of sustainable development in life and educational activities. © Published under licence by IOP Publishing Ltd.

Emergency surgical strategies for patients with acute abdomen during the COVID-19 outbreak

Objective: To investigate the emergency surgical strategies for patients with acute abdomen during the Corona Virus Disease 2019 (COVID-19) outbreak. Methods: The retrospective and descriptive study was conducted. The clinical data of 20 patients with acute abdomen who were admitted to the Union Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology between January 18, 2020 and February 10, 2020 were collected. There were 13 males and 7 females, aged from 25 to 82 years, with an average age of 57 years. All the patients with emergency surgeries received pulmonary computed tomography (CT) examination before surgery, and completed nucleic acid detection in throat swab if necessary. Patients excluded from COVID-19 underwent regular anesthesia, suspected and confirmed cases were selected a proper anesthesia based on their medical condition and surgical procedure. Patients excluded from COVID-19 underwent emergency surgeries following the regular procedure, suspected and confirmed cases underwent emergency surgeries following the three-grade protection. Observation indicators: (1) surgical situations;(2) postoperative situations. Measurement data with normal distribution were represented as average (range). Count data were described as absolute numbers. Results: (1) Surgical situations: of the 20 patients with acute abdomen, 16 patients were excluded from COVID-19, and 4 were not excluded. All the 20 patients underwent emergency abdominal surgeries successfully, of whom 2 received surgeries under epidural anesthesia (including 1 with open appendectomy, 1 with open repair of duodenal bulbar perforation), 18 received surgeries under general anesthesia (including 9 with laparoscopic repair of duodenal bulbar perforation, 3 with open partial enterectomy, 3 with laparoscopic appendectomy, 1 with laparoscopic left hemicolectomy, 1 with laparoscopic right hemicolectomy, 1 with cholecystostomy). The operation time of patients was 32-194 minutes, with an average time of 85 minutes. The volume of intraoperative blood loss was 50-400 mL, with an average volume of 68 mL. (2) Postoperative situations: 16 patients excluded from COVID-19 preopratively were treated in the private general ward postoperatively. One of the 16 patients had fever at the postoperative 5th day and was highly suspected of COVID-19 after an emergency follow-up of pulmonary CT showing multiple ground-glass changes in the lungs. The patient was promptly transferred to the isolation ward for treatment, and results of nucleic acid detection in throat swab showed double positive. Medical history described by the patient showed that the patient and family members were residents of Wuhan who were not isolated at home during the epidemic. There was no way to confirm whether they had a history of exposure to patients with COVID-19. Medical staffs involved in this case did not show COVID-19 related symptoms during 14 days of medical observation. The other 15 patients recovered well postoperatively. The 4 patients who were not excluded from COVID-19 preoperatively based on medical history and results of pulmonary CT examination were directly transferred to the isolation ward for treatment postoperatively. They were excluded from COVID-19 for two consecutive negative results of nucleic acid detection in the throat swab and recovered well. Two of the 20 patients with acute abdomen had postoperative complications. One had surgical incision infection and recovered after secondary closure following opening incision, sterilizing and dressing, the other one had intestinal leakage and was improved after conservative treatment by abdominal drainage. There was no death in the 20 patients with acute abdomen. Conclusions: Patients with acute abdomen need to be screened through emergency forward. Patients excluded from COVID-19 undergo emergency surgeries following the regular procedure, and patients not excluded from COVID-19 undergo emergency surgeries following the three-grade protection. The temperature, blood routine test and other laborat ry examinations are performed to monitor patients after operation, and the pulmonary CT and throat nucleic acid tests should be conducted if necessary. Patients excluded from COVID-19 preopratively are treated in the private general ward postoperatively, and they should be promptly transferred to the isolation ward for treatment after being confirmed. Patients who are not excluded from COVID-19 preoperatively based on medical history should be directly transferred to the isolation ward for treatment postoperatively. Copyright © 2020 by the Chinese Medical Association.