34 research outputs found
H2RBox-v2: Boosting HBox-supervised Oriented Object Detection via Symmetric Learning
With the increasing demand for oriented object detection e.g. in autonomous
driving and remote sensing, the oriented annotation has become a
labor-intensive work. To make full use of existing horizontally annotated
datasets and reduce the annotation cost, a weakly-supervised detector H2RBox
for learning the rotated box (RBox) from the horizontal box (HBox) has been
proposed and received great attention. This paper presents a new version,
H2RBox-v2, to further bridge the gap between HBox-supervised and
RBox-supervised oriented object detection. While exploiting axisymmetry via
flipping and rotating consistencies is available through our theoretical
analysis, H2RBox-v2, using a weakly-supervised branch similar to H2RBox, is
embedded with a novel self-supervised branch that learns orientations from the
symmetry inherent in the image of objects. Complemented by modules to cope with
peripheral issues, e.g. angular periodicity, a stable and effective solution is
achieved. To our knowledge, H2RBox-v2 is the first symmetry-supervised paradigm
for oriented object detection. Compared to H2RBox, our method is less
susceptible to low annotation quality and insufficient training data, which in
such cases is expected to give a competitive performance much closer to
fully-supervised oriented object detectors. Specifically, the performance
comparison between H2RBox-v2 and Rotated FCOS on DOTA-v1.0/1.5/2.0 is
72.31%/64.76%/50.33% vs. 72.44%/64.53%/51.77%, 89.66% vs. 88.99% on HRSC, and
42.27% vs. 41.25% on FAIR1M.Comment: 13 pages, 4 figures, 7 tables, the source code is available at
https://github.com/open-mmlab/mmrotat
A kinetic description of electron beam ejection from spacecraft
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94997/1/grl7005.pd
Pressure-relieving devices for preventing heel pressure ulcers
This is the protocol for a review and there is no abstract. The objectives are as follows: To determine the effects of pressure-relieving devices in preventing heel pressure ulcers
Detecting Rotated Objects as Gaussian Distributions and Its 3-D Generalization
Existing detection methods commonly use a parameterized bounding box (BBox)
to model and detect (horizontal) objects and an additional rotation angle
parameter is used for rotated objects. We argue that such a mechanism has
fundamental limitations in building an effective regression loss for rotation
detection, especially for high-precision detection with high IoU (e.g. 0.75).
Instead, we propose to model the rotated objects as Gaussian distributions. A
direct advantage is that our new regression loss regarding the distance between
two Gaussians e.g. Kullback-Leibler Divergence (KLD), can well align the actual
detection performance metric, which is not well addressed in existing methods.
Moreover, the two bottlenecks i.e. boundary discontinuity and square-like
problem also disappear. We also propose an efficient Gaussian metric-based
label assignment strategy to further boost the performance. Interestingly, by
analyzing the BBox parameters' gradients under our Gaussian-based KLD loss, we
show that these parameters are dynamically updated with interpretable physical
meaning, which help explain the effectiveness of our approach, especially for
high-precision detection. We extend our approach from 2-D to 3-D with a
tailored algorithm design to handle the heading estimation, and experimental
results on twelve public datasets (2-D/3-D, aerial/text/face images) with
various base detectors show its superiority.Comment: 19 pages, 11 figures, 16 tables, accepted by TPAMI 2022. Journal
extension for GWD (ICML'21) and KLD (NeurIPS'21). arXiv admin note: text
overlap with arXiv:2101.1195
Methods for leptospirosis laboratory diagnostics: features of experimentation, advantages and limitations
Leptospirosis is a cosmopolitan natural-focal disease representing a serious problem for the majority of the countries in the world including the Russian Federation because this infection causes a serious economic and social damage. Modern laboratory diagnostics of leptospiroses is based on a complex of bacteriological, immunological and molecularbiological methods used in various combinations depending on the problems and possibilities of the laboratories. At all variety, many methods are not applied in practice and the gold standard still remains the routine serological method. Disease diagnostics is based on a set of epidemiological, epizootological, clinical and pathoanatomical data with obligatory laboratory verification of the diagnosis. However often laboratory verification is retrospective or in general absent. For achievement of the best results in leptospirosis diagnostics, it is necessary to improve the available laboratory methods and to use it in practice. Especial attention should be given to introduction of new molecular technologies that simplify laboratory diagnostics and expand its possibilities
Aspects of Serological Diagnostics of Listeriosis (Literature Review)
The review presents data on the antigenic structure and the current classification of epidemically significant serovariants of Listeria. Description of species-specific properties of serovariants of Listeria, which may be common for two or more species, and common antigens with staphylococci and typhoid and paratyphoid bacteria, are given. It has been shown that only the antigenic scheme of Listeria monocytogenes is of practical interest for medical microbiology. Importance of serotyping in the epidemiological analysis to determine the source of infections and ways of its spreading has been determined. Differences in the designation of serovariants in the diagnosis of listeriosis in medical practice are observed. High level of adaptive properties of Listeria, its ability to reproduce in an abiotic environment, including food, susceptibility of immunodeficient individuals, prevalence of food pathway of infection pose a significant danger of increased sickness rate with listeriosis. Serological diagnostics of Listeria has not been developed in detail, and the existing serological methods are aimed at identifying specific antibodies to listeria. Advantages of the serological method include: quick results and the possibility to study any biological material. Currently available serological methods have a number of disadvantages: low reliability of results and low specificity of the study. The most promising method for identification of a serological group of cultures, according to the world classification, is the multiplex PCR method, based on the correlation between the serogroup of an isolate and the presence of specific open reading frames in its genome
EXAMINATION AND TESTING OF EXPERIMENTAL-PRODUCTION SERIES OF POLYVALENT BRUCELLOSIS SERUM
At present no commercial polyvalent brucellosis serum is produced in Russia. We developed a technology of polyvalent brucellosis high-effective and specific serum production without adsorption. Experimental-production series are obeyed the technical specification project
Designing a Nutrient Medium for the Accumulation of Microbial Mass of Listeria
Background. To obtain reliable results of laboratory studies on the identification of Listeria, the presence of certified diagnostic agglutinating Listeria sera is required. An important step in the manufacturing process of such medical devices for in vitro diagnostics requires effective nutrient media for the accumulation of listeriosis microbe. Aim of the research. To develop an effective nutrient medium for the accumulation of bacterial mass of Listeria. Materials and methods. The object of the study was an experimental culture medium for Listeria cultivation. As a control, we used nutrient agar for the cultivation of microorganisms (fish meal hydrolysate, FMH-agar) and meat-peptone agar with 1 % glucose (MPA with 1 % glucose). The specific activity of nutrient media during cultivation of the test strain Listeria monocytogenes 766 was evaluated using a complex of microbiological methods. Results. The optimal base of the nutrient medium for Listeria cultivation has been selected: pancreatic hydrolysate of river magpie fish (Rutilus rutilus lacustris) and hydrolysate of meat water production waste. The qualitative and quantitative composition of the nutrient medium has been developed, its physical, chemical and biological properties have been studied. It was found that after 24 hours of incubation at 37 °C, the nutrient medium provided the growth of typical Listeria colonies. The germination rate was 85 %, which is higher compared to the growth of the culture on MPA with 1 % glucose and GRM agar by an average of 21 % (p < 0,05). Conclusion. The experimental culture medium for Listeria cultivation provided growth of colonies of the test strain L. monocytogenes 766 with the preservation of characteristic cultural, morphological and biochemical properties, and, in terms of germination and growth rate, exceeded the control media. The developed nutrient medium provides effective growth of Listeria and can be used as a medium for the accumulation of microbial mass
Study of the Effect of a Biologically Active Compound Tris(2-hydroxyethyl)ammonium 4-Chlorophenylsulfanylacetate on the Growth of Listeria monocytogenes and Staphylococcus aureus
Background. Development of nutrient media ensuring the maximum growth rate of pathogens of dangerous infectious diseases while preserving their biological properties is extremely important. A promising direction in this area seems to be the use of synthetic microbial growth biostimulants.The aim of the work is to study the possibility of improving nutrient media for the cultivation of Listeria and Staphylococcus using a biologically active compound tris(2-hydroxyethyl)ammonium 4-chlorophenylsulfanylacetate.Materials and methods. The object of the study was experimental nutrient medium for the cultivation of Listeria used for the culturing of the test strain Listeria monocytogenes 766. As a comparison medium, commercial medium Fraser broth to which agar was added at a concentration of 1.5 %, was used. The test strain Staphylococcus aureus ATCC 6538-P (FDA 209-P) was cultivated on meat-peptone agar with 1% glucose. The compound tris(2-hydroxyethyl) ammonium (4-chlorophenyl)sulfanylacetate at a concentration of 10–4 wt. % was studied as a growth stimulator. A nutrient medium without a stimulant served as a control. The specific activity of nutrient media (germination rate, medium sensitivity, growth rate and stability of the main biological properties of microorganisms) was evaluated by the microbiological method.Results. Studies have shown that the addition of a growth stimulator to nutrient media contributes to the growth of colonies (by 10–50 %) and a decrease in the time of their development. When growth stimulator was added to the nutrient medium for the cultivation of Listeria, the initial growth of colonies of the L. monocytogenes 766 test strain after 12 hours of cultivation and growth of colonies of the test strain S. aureus ATCC 6538-P after 6 hours of cultivation on the meat-peptone agar with 1% glucose was observed.Conclusion. Thus, the addition of a growth biostimulator tris(2-hydroxyethyl)ammonium 4-chlorophenylsulfanyl acetate at a concentration of 10–4 wt. % in the nutrient medium accelerates the growth of Listeria and Staphylococcus, allows to reduce the time of issuance of the analysis result in half
Diagnostic Efficiency of Adsorbed Anthrax Vegetative Fluorescent Immunoglobulins Demonstrated in the Medical Trials
Studied is the diagnostic efficiency (specific activity, sensitivity, specificity, reproducibility) of anthrax vegetative fluorescent immunoglobulins. Based on the data, received in medical trials, this preparation is recommended for registration as a product for medical application in the Russian Federation