Abstract
Most of the existing chest X-ray datasets include labels from a list of findings without specifying their locations on the radiographs. This limits the development of machine learning ...algorithms for the detection and localization of chest abnormalities. In this work, we describe a dataset of more than 100,000 chest X-ray scans that were retrospectively collected from two major hospitals in Vietnam. Out of this raw data, we release 18,000 images that were manually annotated by a total of 17 experienced radiologists with 22 local labels of rectangles surrounding abnormalities and 6 global labels of suspected diseases. The released dataset is divided into a training set of 15,000 and a test set of 3,000. Each scan in the training set was independently labeled by 3 radiologists, while each scan in the test set was labeled by the consensus of 5 radiologists. We designed and built a labeling platform for DICOM images to facilitate these annotation procedures. All images are made publicly available in DICOM format along with the labels of both the training set and the test set.
We report the growth of ZnO nanorods on Si/SiO2 subtrates by the thermal evaporation method at different distances (substrate temperatures) from vapor source to substrates. SEM images showed that ...morphologies of nanorods were significantly affected by distance from the substrate to vapor source. Energy dispersive X-ray spectroscopy (EDS) spectra present change of the ratio of zinc to oxygen in ZnO nanostructures as the substrate temperature varied. X-ray diffraction patterns revealed that the prepared ZnO nanorods are preferentially oriented in the c-axis at lower substrate temperature. The shift towards small angle of the XRD pattern peaks is consistent with the presence of the redundant zinc and the lack oxygen in the ZnO lattice. The photoluminescence (PL) spectra of the ZnO nanorods show beside the near band edge UV emission, a very broad emission ranges from green to near-infrared (NIR). The NIR emission is interpreted as due to the transition of carriers between radiative recombination centers related to Zn interstitials and oxygen interstitials.
•ZnO nanorods were grown by thermal evaporation method at different temperatures.•Morphologies of ZnO nanorods were strongly affected by substrate temperature.•The depth level emission presents broad bands from green to infrared region simultaneously.•The depth level emitting at long wavelength region enhances as reducing growth temperature.•Near-infrared emission from ZnO nanorods grown by thermal evaporation method.
In this study, a milling experiment was performed, with 3x13 steel selected as the experimental material along with TiAlN coated inserts. The Box-Behnken method was used to design the experimental ...matrix with a total of eighteen experiments. Cutting speed, feed amount, and depth of cut were selected as the input parameters. Three regression models of surface roughness have been established, one using the experimentally measured surface texture, one using the Johnson transform to convert the surface texture data, and one using Box-Cox transformation to convert the surface texture data. A comparison of the accuracy of the three models was performed. The results show that the model using the Box-Cox transformation has the highest accuracy, followed by the model using the Johnson transformation. In addition, the influence of cutting parameters on surface roughness is also discussed in detail.
SCM440 steel is a commonly used material for making plastic injection molds and components such as gears, transmission shafts, rolling pins, etc. Surface roughness has a direct influence on the ...workability and durability of the parts and/or components, while the Material Removal Rate (MRR) is a parameter that is used to evaluate the productivity of the machining process. Furnished products with small surface roughness and large MRR is the desired result by all milling processes. In this paper, the determination of the values of input parameters is studied in order to ensure that during the process of milling SCM440 steel, it will have the smallest surface roughness and the largest MRR. There are five parameters that are required to be determined, namely the cutting insert material, the tool nose radius, the cutting speed, the feed rate, and the cutting depth. The Taguchi method was applied to design the experimental matrix with a total of 27 experiments. Result analysis determined the influence of the input parameters on surface roughness and MRR. The Data Envelopment Analysis-based Ranking (DEAR) method was applied to determine the optimal value of the input parameters, which were used to conduct the milling experiments to re-evaluate their suitability.
Summary
Bats and rodents are being increasingly recognized as reservoirs of emerging zoonotic viruses. Various studies have investigated bat viruses in tropical regions, but to date there are no data ...regarding viruses with zoonotic potential that circulate in bat and rat populations in Viet Nam. To address this paucity of data, we sampled three bat farms and three wet markets trading in rat meat in the Mekong Delta region of southern Viet Nam. Faecal and urine samples were screened for the presence of RNA from paramyxoviruses, coronaviruses and filoviruses. Paramyxovirus RNA was detected in 4 of 248 (1%) and 11 of 222 (4.9%) bat faecal and urine samples, respectively. Coronavirus RNA was detected in 55 of 248 (22%) of bat faecal samples; filovirus RNA was not detected in any of the bat samples. Further, coronavirus RNA was detected in 12 of 270 (4.4%) of rat faecal samples; all samples tested negative for paramyxovirus. Phylogenetic analysis revealed that the bat paramyxoviruses and bat and rat coronaviruses were related to viruses circulating in bat and rodent populations globally, but showed no cross‐species mixing of viruses between bat and rat populations within Viet Nam. Our study shows that potentially novel variants of paramyxoviruses and coronaviruses commonly circulate in bat and rat populations in Viet Nam. Further characterization of the viruses and additional human and animal surveillance is required to evaluate the likelihood of viral spillover and to assess whether these viruses pose a risk to human health.
Summary
We investigated episodes of suspected highly pathogenic avian influenza (HPAI)‐like illness among 12 meat duck flocks in two districts in Tien Giang province (Mekong Delta, Vietnam) in ...November 2013. In total, duck samples from 8 of 12 farms tested positive for HPAI virus subtype A/haemagglutinin 5 and neuraminidase 1 (H5N1) by real‐time RT‐PCR. Sequencing results confirmed clade of 2.3.2.1.c as the cause of the outbreaks. Most (7/8) laboratory‐confirmed positive flocks had been vaccinated with inactivated HPAI H5N1 clade 2.3.4 vaccines <6 days prior to onset of clinical signs. A review of vaccination data in relation to estimated production in the area suggested that vaccination efforts were biased towards larger flocks and that vaccination coverage was low 21.2% ducks vaccinated with two shots (range by district 7.4–34.9%). The low‐coverage data, the experimental evidence of lack of cross‐protection conferred by the currently used vaccines based on clade 2.3.4 together with the short lifespan of meat duck flocks (60–70 days), suggest that vaccination is not likely to be effective as a tool for control of H5N1 infection in meat duck flocks in the area.
Bioassay-directed fractionation led to the isolation of 12 compounds from a sample of the dried leaves, twigs, and stems of Grewia bilamellata. Five of the isolates, 3α,20-lupandiol (1), grewin (2), ...nitidanin (4), 2α,3β-dihydroxy-olean-12-en-28-oic acid (5), and 2,6-dimethoxy-1-acetonylquinol (6), showed varying degrees of in vitro antimalarial activity against Plasmodium falciparum, but were devoid of significant cytotoxicity to the human oral epidermoid KB cancer cell line. Of the 12 isolates, compounds 1, 2, and 3 (bilagrewin) were determined to be a new triterpene, a new coumarinolignan, and a new neolignan, respectively. Other known compounds isolated in this study were 8-O-4‘ neolignan guaiacylglycerol-β-coniferyl ether isomers (threo and erythro), cleomiscosin D, icariol A2, ciwujiatone, and daucosterol. The structures of 1−3 were elucidated and identified on the basis of spectroscopic data including 1D and 2D NMR analysis.
Bioassay-directed fractionation led to the isolation of 14 compounds, six of which possess antimalarial activity, from the dried leaves and stems of Rhaphidophora decursiva. Polysyphorin (1) and ...rhaphidecurperoxin (6) showed strong activities against Plasmodium falciparum. Rhaphidecursinol A (2), rhaphidecursinol B (3), grandisin (4), and epigrandisin (5) were less active against the same organism. Among the isolates, rhaphidecursinol A (2) and rhaphidecursinol B (3) were determined to be new neolignans, and rhaphidecurperoxin (6) is a new benzoperoxide. Known compounds isolated include polysyphorin (1), grandisin (4), epigrandisin (5), (+)-medioresinol, (-)-pinoresinol, (-)-syringaresinol, (+)-glaberide I, (+)-dehydrovomifoliol, (-)-liliolide, (-)-hydroxydihydrobovolide, and N-butylbenzamide, of which compound 1 appears worthy of further evaluation as an antimalarial agent. Structure elucidation and identification were accomplished by spectroscopic means including 1D and 2D NMR analyses.
Patients with end-stage renal failure are susceptible to dry eye disease. This study explores the relationship between dry eye disease and influence factors.
The control group consisted of 57 healthy ...subjects who were kidney donors. They were of the same age and sex as the kidney transplant recipients. The outcome variable was the dry eye condition of the participants. The Schirmer test confirmed dry eye disease, TBUT (breakup time test), and the Eye Surface Disease Index (OSDI) questionnaire, using linear regression to evaluate the association.
The total number of subjects was 146 (89 kidney recipients and 57 kidney donors). When univariate analysis found the level of visual acuity, the age group involved was statistically significant, while the other factors were not statistically significant. In multivariable logistic regression analysis, age (odds ratio: 2.8, p<0.05), smoking history (odd ratio: 0.1, p<0.05), corneal conjunctival calcification (odd ratio: 0.2, p<0.05); central corneal thickness (odd ratio: 1.02, p<0.05) is considered to be an influence factor for disease progression.
Age group, smoking history, corneal central thickness, and conjunctival calcification are factors for dry eye disease in patients preparing to receive a kidney. These results reinforce the evidence for multifactorial dry eye disease in patients with renal impairment.
The use of 3D (three-dimensional) scanning in calculating tree's volume is discussed and suitable equations are fitted for estimating stand volume based on stem diameter at breast height (DBH) and ...height in the form of power and logarithmic functions. One hundred eighty-four individuals of Hopea odorata, Dipterocarpus alatus and Afzelia xylocarpa were scanned. Then, 3D images were used to calculate an individual tree's volume, based on sectioning the main stem and branches by assuming the cylinder of each section. The results indicated that 3D image calculations underestimated volume by 2.1-4.8% compared to the water displacement method by testing spiral branches of 4.3-15.7 cm diameter. The logarithmic function is the best-fitted model for each species and the combination of three species. A. alatus, H. odorata and combination of three species require both DBH and height, while A. xylocarpa needs only DBH in volume estimation. All four best fitted equations have Adjusted R-Squared > 0.88 and underestimate < 0.9% 3D volume. The smallest underestimate of 0.02% 3D volume belongs to the best-fitted equation for combination of three species, indicating the potentiality of using a combination of three species equation for estimating the volume of all species, especially in natural forests. It is concluded the suitability of using the 3D scanning technique for calculating individual tree's volume with high accuracy and establishing volume equations for multiple species applications, especially in the tropical forest.
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