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The COVID-19 pandemic presented enormous data challenges in the United States. Policy makers, epidemiological modelers, and health researchers all require up-to-date data on the pandemic and relevant public behavior, ideally at fine spatial and temporal resolution. The COVIDcast API is our attempt to fill this need: Operational since April 2020, it provides open access to both traditional public health surveillance signals (cases, deaths, and hospitalizations) and many auxiliary indicators of COVID-19 activity, such as signals extracted from deidentified medical claims data, massive online surveys, cell phone mobility data, and internet search trends. These are available at a fine geographic resolution (mostly at the county level) and are updated daily. The COVIDcast API also tracks all revisions to historical data, allowing modelers to account for the frequent revisions and backfill that are common for many public health data sources. All of the data are available in a common format through the API and accompanying R and Python software packages. This paper describes the data sources and signals, and provides examples demonstrating that the auxiliary signals in the COVIDcast API present information relevant to tracking COVID activity, augmenting traditional public health reporting and empowering research and decision-making.

Visual simultaneous localization and mapping (VSLAM) is pivotal for intelligent mobile robots. VSLAM systems can be used to identify scenes by obtaining massive amounts of redundant texture information from the environment. However, VSLAM faces a major challenge in dynamic low-light environments, in which the extraction of feature points is often difficult, leading to tracking failure with mobile robots. Therefore, we developed a method to improve the feature point extraction method used for VSLAM. We first used the contrast limited adaptive histogram equalization (CLAHE) method to increase the contrast in low-light images, allowing for the extraction of more feature points. Second, in order to increase the effectiveness of the extracted feature points, the redundant feature points were removed. We developed three conditions to filter the feature points. Finally, the proposed method was tested on popular datasets (e.g., TUM and OpenLORIS-Scene), and the results were compared with those of several traditional methods. The results of the experiments showed that the proposed method is feasible and highly robust in dynamic low-light environments. [ABSTRACT FROM AUTHOR]

Objective To investigate the reliability of using virtual articulator in the fabrication of zirconia crowns for tetracycline discolored teeth. Methods To treat the patient with serious tetracycline stained teeth, we use zirconia crowns to shield the stained abutment teeth. To retain the characteristics of patient′s original occlusal contacts, mean⁃ while, to establish a stable and evenly distributed occlusal contacts, we recorded the functional movements of the pa⁃ tient′s jaw before preparing the teeth and transferred this relations to a physical articulator. Afterwards, relationship of the upper and lower arches was scanned through a specified fixature. Then we can customized the fabrication of the oc⁃ clusal contacts of the restorations conveniently and efficiently with virtual articulator in CAD/CAM system. Results When the final restorations were inserted , a charming smile was achieved on patient′s face with satisfactory esthetics. With the application of virtual articulator in designing process, we made evenly distributed and stable bilateral occlusal contacting spots, smooth protrusive and lateral guidance on the lingual aspects of the upper anteriors. One year follow⁃ up, this patient was observed in good oral hygiene, and was satisfied with her esthetic and functional outcome. The soft tissue around the restorations was assessed to be healthy and no signs of inflammation. Conclusion Applying the virtu⁃ al articulator kits in CAD/CAM system in designing and fabricating the function⁃driven restorations could be an efficient way to obtain an satisfactory long⁃term outcome.

Simultaneous localization and mapping (SLAM) plays a crucial role in the field of intelligent mobile robots. However, the traditional Visual SLAM (VSLAM) framework is based on strong assumptions about static environments, which are not applicable to dynamic real-world environments. The correctness of re-localization and recall of loop closure detection are both lower when the mobile robot loses frames in a dynamic environment. Thus, in this paper, the re-localization and loop closure detection method with a semantic topology graph based on ORB-SLAM2 is proposed. First, we use YOLOv5 for object detection and label the recognized dynamic and static objects. Secondly, the topology graph is constructed using the position information of static objects in space. Then, we propose a weight expression for the topology graph to calculate the similarity of topology in different keyframes. Finally, the re-localization and loop closure detection are determined based on the value of topology similarity. Experiments on public datasets show that the semantic topology graph is effective in improving the correct rate of re-localization and the accuracy of loop closure detection in a dynamic environment. [ABSTRACT FROM AUTHOR]

Abstract Background The VP3 protein of goose parvovirus (GPV) or Muscovy duck parvovirus (MDPV), a major structural protein, can induce neutralizing antibodies in geese and ducks, but monoclonal antibodies (MAbs) against VP3 protein has never been characterized. Results Three hybridoma cell lines secreting anti-GPV VP3 MAbs were obtained and designated 4A8, 4E2, and 2D5. Immunoglobulin subclass tests differentiated them as IgG2b (4A8 and 4E2) and IgG2a (2D5). Dot blotting assays showed that three MAbs reacted with His-VP3 protein in a conformation-independent manner. A competitive binding assay indicated that the MAbs delineated two epitopes, A and B of VP3. Immunofluorescence assay showed that MAbs 4A8, 4E2, and 2D5 could specifically bind to goose embryo fibroblast cells (GEF) or duck fibroblast cells (DEF) infected with GPV and MDPV. Dot blotting also showed that the MAbs recognized both nature GPV and MDPV antigen. Western blotting confirmed that the MAbs recognized VP3 proteins derived from purified GPV and MDPV particles. The MAbs 4A8 and 2D5 had universal reactivity to heterologous GPV and MDPV tested in an antigen-capture enzyme-linked immunosorbent assay. Conclusions Preparation and characterization of these the MAbs suggests that they may be useful for the development of a MAb-capture ELISA for rapid detection of both GPV and MDPV. Virus isolation and PCR are reliable for detecting GPV and MDPV infection, but these procedures are laborious, time-consuming, and requiring instruments. These diagnosis problems highlight the ongoing demand for rapid, reproducible, and automatic methods for the sensitive detection of both GPV and MDPV infection.

Lysophosphatidic acid is a serum-derived growth factor that is involved in wound healing. Although in its infancy, a growing body of evidence has demonstrated that lysophosphatidic acid exerts a potentially significant role in regulating bone cell biology. However, previous studies mainly focused on the osteoinductive potential of lysophosphatidic acid, its effects on bone tissue vascularization, another essential element during bone regeneration, remains ill-defined so far. Here in this study, we examined the effects of lysophosphatidic acid on osteogenic differentiation as well as the angiogenesis-inducing capacity of pre-osteoblasts, a cell population that coordinates osteogenic and angiogenic processes in bone regenerating niche. Our results showed that treatment of MC3T3-E1 pre-osteoblastic cells with lysophosphatidic acid enhanced alkaline phosphatase activity and matrix mineralization, demonstrating in vitro osteoblastic differentiation. Of particular importance was the finding that vascular endothelial growth factor secretion also increased after lysophosphatidic acid treatment. Lysophosphatidic acid conditioned media of MC3T3-E1 cells was capable of promoting angiogenic behavior of endothelial cells, as evidenced by stimulating proliferation, migration, and tube formation. Besides, inhibition of LPA1/3 receptor abolished lysophosphatidic acid-induced elevation of the osteogenic and angiogenic capability of pre-osteoblasts. Our research demonstrated the important role of lysophosphatidic acid in coupling osteogenesis and angiogenesis during bone remodeling through orchestrating pre-osteoblast behavior, and implications therein for novel and effective treatment strategies for bone regeneration success. [ABSTRACT FROM AUTHOR]

[Objective] The paper to investigate the effects of pelleted total mixed ration of different particle size on production performance and serum biochemical index of fattening Hainan black goats. [Method] Thirty-six fattening Hainan black goats with the same genetic backgrounds and similar initial weight of (19.02±0.22) kg were randomly divided into three treatments. Goats were fed with Juncao+concentrate (control group), pelleted total mixed ration I (particle size 6 mm, experimental group I) and II (particle size 5 mm, experimental group II), respectively. The trial lasted 45 d. [Result] (1) The final weight and daily gain of experimental group II were significantly higher than those of control group (P<0.05), and the daily gain of experimental group II was also higher than that of experimental group I (P<:0.05); the feed intake of experimental group II was markedly higher than that of control group (P<0.05), but was significantly lower than that of experimental group I (P<0.05). The feed/gain ratio of experimental group II was significantly lower than those of control group and experimental group I (P<0.05). (2) The feed gain cost of experimental group II was markedly lower than that of control group (P<0.05), but the gross profit was significantly higher than those of control group and experimental group I (P<0.05). (3) Compared with the control group, the serum total protein content of experimental group II increased markedly (P<0.05) while the urea nitrogen level decreased (P>0.05). [Conclusion] The pelleted total mixed ration with the particle size of 5 mm obtained better fattening effect, and obviously improved the serum total protein level. [ABSTRACT FROM AUTHOR]

[Objective] This paper was to study effects of pelleted total mixed ration with different concenlrate-roughage ratios on production performance and serum biochemical parameters of fattening Hainan black goats. [Method] Thirty-six fattening Hainan black goats with the same genetic background and similar initial weight of (14.08+0.13) kg were randomly assigned into three treatments. Goats were fed with Juncao + concentrate (control group), pelleted total mixed ration I (concentrate: roughage 50;50, group I) and II (concentrate: roughage 45;55, group II), respectively. The test lasted 45 d. [Result] The final weight, daily gain and feed intake of rams in experimental group 1 were significantly higher than those of control group and experimental group II (P<0.05); the final weight and daily gain of rains in experimental group I were also markedly higher than those of experimental group II (P<0.05); the feed/gain of rams in experimental group I was significantly lower than those in control group and experimental group If (P<0.05). The feed gain cost of rams in experimental group T was markedly lower than that in experimental group TT (P<0.05), but was significantly higher than that in experimental group 1 (P<0.05); the gross profit of rams in experimental group 1 wras significantly higher than those in control group and experimental group 11 (P<0.05). Compared with control group and experimental group 11, the serum total protein and glucose levels in experimental group 11 increased significantly (P<0.05), but the urea nitrogen content reduced (P>0.05). [Conclusion] When the concentrate-roughage ratio ol pelleted total mixed ration was 50:50, the fattening effect of Hainan black goal was better, and the serum total protein and glucose levels were evidently improved. [ABSTRACT FROM AUTHOR]

[Objective] The paper was to study the effects on growth performance and feed digestibility of Hainan black pigs by adding lysine in low protein diet. [Method] A total of 36 Hainan black pigs with the body weight of (46341306) kg were randomly divided into three groups: control group (protein level 15%, lysine level 0.83%), experimental group I (protein level 13%, 0.83%), and experimental group II (protein level 13%, lysine level 1.03), each group had three replicates of four pigs. The trial lasted 35 d. [Result] The growth performance of Hainan black pig in group [I had no significant difference with that in control group (P>0.05). The apparent digestibility of crude protein and phosphorus of Hainan black pigs in Group II increased significantly (P<0.05), which were increased by 10.08% and 11.85% respectively compared to the control group; the apparent digestibility of calcium was increased, but the difference was not significant (P>0.05). [Conclusion] It will not reduce the growth performance of Hainan black pig when the protein level of diet is reduced by 2% and the lysine level is increased to 1.03%. It is recommended that the diet can be used in the production of Hainan black pig. [ABSTRACT FROM AUTHOR]