Early detection of malignant thyroid nodules leading to patient-specific treatments can reduce morbidity and mortality rates. Currently, thyroid specialists use medical images to diagnose then follow ...the treatment protocols, which have limitations due to unreliable human false-positive diagnostic rates. With the emergence of deep learning, advances in computer-aided diagnosis techniques have yielded promising earlier detection and prediction accuracy; however, clinicians' adoption is far lacking. The present study adopts Xception neural network as the base structure and designs a practical framework, which comprises three adaptable multi-channel architectures that were positively evaluated using real-world data sets. The proposed architectures outperform existing statistical and machine learning techniques and reached a diagnostic accuracy rate of 0.989 with ultrasound images and 0.975 with computed tomography scans through the single input dual-channel architecture. Moreover, the patient-specific design was implemented for thyroid cancer detection and has obtained an accuracy of 0.95 for double inputs dual-channel architecture and 0.94 for four-channel architecture. Our evaluation suggests that ultrasound images and computed tomography (CT) scans yield comparable diagnostic results through computer-aided diagnosis applications. With ultrasound images obtained slightly higher results, CT, on the other hand, can achieve the patient-specific diagnostic design. Besides, with the proposed framework, clinicians can select the best fitting architecture when making decisions regarding a thyroid cancer diagnosis. The proposed framework also incorporates interpretable results as evidence, which potentially improves clinicians' trust and hence their adoption of the computer-aided diagnosis techniques proposed with increased efficiency and accuracy.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A new group of thin film metallic glasses (TFMGs) have been reported to exhibit properties different from conventional crystalline metal films, though their bulk forms are already well-known for high ...strength and toughness, large elastic limits, and excellent corrosion and wear resistance because of their amorphous structure. In recent decades, bulk metallic glasses have gained a great deal of interest due to substantial improvements in specimen sizes. In contrast, much less attention has been devoted to TFMGs, despite the fact that they have many properties and characteristics, which are not readily achievable with other types of metallic or oxide films. Nevertheless, TFMGs have been progressively used for engineering applications and, thus, deserve to be recognized in the field of thin film coatings. This article will thus discuss both properties and applications of TFMGs including a review of solid-state amorphization upon annealing, the glass-forming ability improvement due to thin film deposition, and mechanical properties, including residual stress, hardness and microcompression, adhesion, and wear resistance. Potential applications and simulations will also be discussed.
An up‐to‐date map of the Antarctic Circumpolar Current (ACC) fronts is constructed from the latest version of mean dynamic topography (MDT) from satellite altimetry and reveals the narrowest ACC ...width in the Udintsev Fracture Zone (UFZ), with the strongest concentration of the three major ACC fronts within a limited distance as short as 170 km, about 40% narrower than that at Drake Passage. At 144°W, at the entrance of the UFZ, which lies between the Pacific‐Antarctic Ridge (PAR) and its eastwardly offset segment (offset PAR segment), there is a triple confluence of the Subantarctic Front, Polar Front, and Southern ACC Front . Downstream of this longitude, the Subantarctic Front progressively meanders northward over the relatively shallow offset PAR segment before channeling through the Eltanin Fracture Zone, thus diverging from the Polar Front which proceeds through the UFZ. In situ observations from two recent cruises at 144°W confirm the satellite altimetry‐derived frontal circulation in the UFZ region and yield a baroclinic transport relative to the bottom of 113 × 106 m3/s, comparable to that through Drake Passage. The hydrographic sections show no Antarctic bottom water colder than 0.2 °C. Characteristics of major water masses are described, and the implications for their potential downstream modifications at Drake Passage are discussed in terms of the meridional overturning circulation across the ACC. Mesoscale eddy activity with periods shorter than 90 days is predominantly concentrated in the immediate downstream area of the offset PAR segment, suggesting a substantial poleward eddy heat flux there.
Key Points
The Antarctic Circumpolar Current is only 170 km wide in the Udintsev Fracture Zone, forming the narrowest circumpolar choke point
First observations of high‐quality hydrography in the Udintsev Fracture Zone show no Antarctic bottom water colder than 0.2 °C
The Udintsev Fracture Zone is a suitable site for a long‐term monitoring of the Antarctic Circumpolar Current
ABSTRACT We conduct a multiwavelength continuum variability study of the Seyfert 1 galaxy NGC 5548 to investigate the temperature structure of its accretion disk. The 19 overlapping continuum light ...curves ( to ) combine simultaneous Hubble Space Telescope, Swift, and ground-based observations over a 180 day period from 2014 January to July. Light-curve variability is interpreted as the reverberation response of the accretion disk to irradiation by a central time-varying point source. Our model yields the disk inclination , temperature K at 1 light day from the black hole, and a temperature-radius slope ( ) of . We also infer the driving light curve and find that it correlates poorly with both the hard and soft X-ray light curves, suggesting that the X-rays alone may not drive the ultraviolet and optical variability over the observing period. We also decompose the light curves into bright, faint, and mean accretion-disk spectra. These spectra lie below that expected for a standard blackbody accretion disk accreting at .
The ring-opening process is the rate-determining step for photocatalytic decomposition of aromatic volatile organic compounds (VOCs). However, the ring-opening pathway has not been fully revealed, ...which enables efficient photocatalytic VOC degradation. Taking the photocatalytic toluene degradation as a typical case, the ring-opening pathway and regulation strategy were systematically investigated and proposed with an aim to regulate the rate-determining step and accelerate the reaction rates. Herein, BiOCl with tailored facets was designed as a model photocatalyst to clarify the mechanism of photocatalytic toluene degradation. Theoretical calculations and in situ DRIFTS technology were closely combined to dynamically predict and monitor the photocatalytic toluene degradation reactions. It is revealed that the lowest energy barrier was precisely located at the ring-opening of benzoic acid which was generated from toluene oxidation. This result implied that the benzyl must be fully oxidized to benzoic acid to elevate the ring-opening reaction rates. Moreover, the alternative charge arrangement on the {010} facet of BiOCl facilitated the benzyl oxidation and selectivity for benzoic acid ring-opening reactions, subsequently resulting in remarkably enhanced photocatalytic efficiency, exceeding that of the {001} facet by 100% towards toluene decomposition. This work demonstrates that probing and tailoring the ring-opening pathway are vital to increase the overall toluene decomposition efficiency and could provide new insights into the understanding of the photocatalytic reactions in VOC degradation.
Although the clinical features of the Isocitrate dehydrogenase 2 (IDH2) mutation in acute myeloid leukemia (AML) have been characterized, its prognostic significance remains controversial and its ...stability has not been investigated. We analyzed 446 adults with primary non-M3 AML and found IDH2 R172, R140 and IDH1 R132 mutations occurred at a frequency of 2.9, 9.2 and 6.1%, respectively. Compared with wild-type IDH2, mutation of IDH2 was associated with higher platelet counts, intermediate-risk or normal karyotype and isolated +8, but was inversely correlated with expression of HLA-DR, CD34, CD15, CD7 and CD56, and was mutually exclusive with WT1 mutation and chromosomal translocations involving core-binding factors. All these correlations became stronger when IDH1 and IDH2 mutations were considered together. Multivariate analysis revealed IDH2 mutation as an independent favorable prognostic factor. IDH2(-)/FLT3-ITD(+) genotype conferred especially negative impact on survival. Compared with IDH2 R140 mutation, IDH2 R172 mutation was associated with younger age, lower white blood cell count and lactate dehydrogenase level, and was mutually exclusive with NPM1 mutation. Serial analyses of IDH2 mutations at both diagnosis and relapse in 121 patients confirmed high stability of IDH2 mutations. In conclusion, IDH2 mutation is a stable marker during disease evolution and confers favorable prognosis.
Development of efficient and durable oxygen evolution reaction (OER) catalysts has a direct impact on the water splitting efficiency and cost effectiveness. In this work, we report the successful ...synthesis of a new Ni(OH)
2
structure, strain-stabilized Ni(OH)
2
nanoribbons (NR-Ni(OH)
2
) two to three layers thick, with widths of 2-5 nm,
via
an electro-oxidation route. Conventional Ni(OH)
2
usually has negligible OER activity, while NR-Ni(OH)
2
shows high activity for the oxygen evolution reaction and an overpotential of 162 millivolts and furthermore exhibits long-term stability in alkaline electrolyte. The substantial reduction in the overpotential of NR-Ni(OH)
2
is due to its easier OOH* adsorption by the active four-coordinated Ni edge sites. The enhanced catalytic activity of NR-Ni(OH)
2
makes it an excellent candidate for industrial applications.
Development of efficient and durable oxygen evolution reaction (OER) catalysts has a direct impact on the water splitting efficiency and cost effectiveness.
Concentrations and distributions of organic carbon (OC) and elemental carbon (EC) in atmospheric particles were measured at 8 sites in four cities (Hong Kong, Guangzhou, Shenzhen and Zhuhai) of Pearl ...River Delta Region (PRDR), China during two winter months (January and February, 2002). PM
2.5 and PM
10 samples were collected on pre-fired quartz filters with mini-volume samplers and analyzed using thermal optical reflectance (TOR) method. Average PM
2.5 and PM
10 level were 72.6 and 111.5
μg
m
−3, respectively, with PM
2.5 constituting 70.4% of the PM
10 mass. The average OC and EC concentrations in PM
2.5 were 14.7 and 6.1
μg
m
−3, respectively, while those in PM
10 were 19.7 and 7.8
μg
m
−3, respectively. The carbonaceous aerosol accounted for 40.2% of the PM
2.5 and 35.9% of the PM
10. The average OC/EC ratio was 2.4 for PM
2.5 and 2.5 for PM
10, which are comparable with most urban cities in the world. The OC and EC in PRDR were found to be strongly correlated (correlation coefficients >0.7). Secondary organic carbon was found to constitute 42.6% and 38.4% of the total organic carbon in PM
2.5 and PM
10, respectively.
Clinical studies and mathematical models predict that, to achieve malaria elimination, combination therapies will need to incorporate drugs that block the transmission of Plasmodium falciparum sexual ...stage parasites to mosquito vectors. Efforts to measure the activity of existing antimalarials on intraerythrocytic sexual stage gametocytes and identify transmission-blocking agents have, until now, been hindered by a lack of quantitative assays. Here, we report an experimental system using P. falciparum lines that stably express gametocyte-specific GFP-luciferase reporters, which enable the assessment of dose- and time-dependent drug action on gametocyte maturation and transmission. These studies reveal activity of the first-line antimalarial dihydroartemisinin and the partner drugs lumefantrine and pyronaridine against early gametocyte stages, along with moderate inhibition of mature gametocyte transmission to Anopheles mosquitoes. The other partner agents monodesethyl-amodiaquine and piperaquine showed activity only against immature gametocytes. Our data also identify methylene blue as a potent inhibitor of gametocyte development across all stages. This thiazine dye almost fully abolishes P. falciparum transmission to mosquitoes at concentrations readily achievable in humans, highlighting the potential of this chemical class to reduce the spread of malaria.
Background. Better understanding of complications and outcomes of adults hospitalized with respiratory syncytial virus (RSV) infection is necessary. Methods. A retrospective cohort study was ...conducted on all adults (≥18 years) admitted to 3 acute care general hospitals in Hong Kong with virologically confirmed RSV infection during 2009–2011 (N = 607). Adults hospitalized for seasonal influenza during the period were used for comparison (n = 547). Both infections were prospectively diagnosed following a standard protocol. Independent reviews of chest radiographs were performed by radiologists. Main outcome measures were all-cause death, respiratory failure requiring ventilatory support, and hospitalization duration. Cox proportional hazards models were used for analyses. Results. The mean age of RSV patients was 75 (SD, 16) years; 87% had underlying conditions. Lower respiratory and cardiovascular complications were diagnosed in 71.9% (pneumonia, 42.3%; acute bronchitis, 21.9%; chronic obstructive pulmonary disease/asthma exacerbation, 27.3%) and 14.3% of patients, respectively; 12.5% had bacterial superinfections. Supplemental oxygen and ventilatory support were required in 67.9% and 11.1%, respectively. Crude all-cause mortality was 9.1% and 11.9% within 30 days and 60 days, respectively; mean length of stay of survivors was 12 (SD, 13) days. Advanced age, radiographic pneumonia, requirement for ventilation, bacterial superinfection, and elevated urea level and white blood cell count were independently associated with poorer survival. Systemic corticosteroid use was associated with longer hospitalization and secondary infections. The overall outcomes of survival and length of stay were not significantly different from those in influenza. Conclusions. RSV can cause severe lower respiratory complications in older adults, resulting in respiratory failure, prolonged hospitalization, and high mortality similar to seasonal influenza. Corticosteroids did not seem to improve outcomes. The unmet need for antiviral therapy and vaccination against RSV in adults should be promptly addressed.
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